Bitrate efficient transport through distributed antenna systems

A distributed antenna system includes a host unit configured to receive downlink wireless network information from a radio access network interface and at least one antenna unit communicatively coupled to the host unit by at least one digital communication link. Host unit is configured to convert downlink wireless network information received from radio access network interface from first protocol layer to second protocol layer. Second protocol layer uses relevant bits more efficiently than first protocol layer. Host unit is configured to communicate downlink wireless network information to at least one antenna unit across at least one digital communication link. At least one antenna unit is configured to convert downlink wireless network information communicated from host unit from second protocol layer to downlink radio frequency signals. At least one antenna unit is configured to communicate downlink radio frequency signals wirelessly using at least one antenna.

BACKGROUND

Distributed Antenna Systems (DAS) are used to distribute wireless signal coverage into buildings or other substantially closed environments. For example, a DAS may distribute antennas within a building. The antennas are typically connected to a radio frequency (RF) signal source, such as a service provider. Various methods of transporting the RF signal from the RF signal source to the antenna have been implemented in the art.

SUMMARY

A distributed antenna system includes a host unit configured to receive downlink wireless network information from a radio access network interface and at least one antenna unit communicatively coupled to the host unit by at least one digital communication link. The host unit is configured to convert the downlink wireless network information received from the radio access network interface from a first protocol layer to a second protocol layer. The second protocol layer uses relevant bits more efficiently than the first protocol layer. The host unit is configured to communicate the downlink wireless network information to the at least one antenna unit across the at least one digital communication link. The at least one antenna unit is configured to convert the downlink wireless network information communicated from the host unit from the second protocol layer to downlink radio frequency signals. The at least one antenna unit is configured to communicate the downlink radio frequency signals wirelessly using at least one antenna.

In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the exemplary embodiments. Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

The embodiments described below describe a distributed antenna system (DAS) and components within the distributed antenna system (DAS). The distributed antenna system is connected to at least one radio access network (RAN) through at least one radio access network (RAN) interface. In exemplary embodiments, the distributed antenna system includes a distributed antenna system host that interfaces with the at least one radio access network (RAN) interface and converts wireless network information to a more efficient format for transport across at least one medium to at least one antenna unit that converts the wireless network information to a radio frequency signal and communicates it wirelessly using at least one antenna. More specifically, in some embodiments medium access control (MAC) protocol data units (PDUs) are transported instead of baseband IQ samples because the wireless network information is more efficiently transported in MAC PDUs than baseband IQ samples. The ability to transmit the wireless network information in MAC PDUs more efficiently than the baseband IQ samples enables lower bandwidth media to be used, such as Category building cabling such as Category 5, Category 5e, Category 6, Category 6A and Category 7. The ability to transmit the MAC PDUs more efficiently than the baseband IQ samples is essentially a compression technique that enables more data to transmitted over the media. In exemplary embodiments, synchronization information, timing information, power level, signal gain and/or other additional overhead is transmitted in addition to the wireless network information. In exemplary embodiments, wireless network information (or cellular network information) is represented in different ways by the different protocol layers. The wireless network information is the same, but it is formatted differently using different headers, control words, error control bits, etc. that are added/removed by the different protocol layers throughout the entire system. While described using the term distributed antenna system (DAS) herein, it is understood that this description also applies to other wireless distribution technologies and networks, such as distributed base stations, remote radio heads, and/or a centralized radio access network (CRAN, also known as Cloud-RAN and coordinated RAN). In exemplary embodiments, the antenna unit is embodied as a remote radio head. In exemplary embodiments, the radio access network interface is embodied as a baseband unit in a distributed base station and/or a centralized radio access network (CRAN).

In exemplary embodiments, radio access technologies may operate using various wireless protocols and in various bands of frequency spectrum. The systems and methodologies described herein apply equally to a number of radio access technologies (RAT), though it is more beneficial for radio access technologies (RAT) that are substantially less efficient with bandwidth at one layer than another. For example, the radio access technologies (RAT) may include, but are not limited to, 800 MHz cellular service, 1.9 GHz Personal Communication Services (PCS), Specialized Mobile Radio (SMR) services, Enhanced Special Mobile Radio (ESMR) services at both 800 MHz and 900 MHz, 1800 MHz and 2100 MHz Advanced Wireless Services (AWS), 700 MHz uC/ABC services, two way paging services, video services, Public Safety (PS) services at 450 MHz, 900 MHz and 1800 MHz Global System for Mobile Communications (GSM), 2100 MHz Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), 3rd Generation Partnership Projects (3GPP) Long Term Evolution (LTE), High Speed Packet Access (HSPA), or other appropriate communication services. The system described herein are capable of transporting both Single Input Single Output (SISO) and Multiple Input Multiple Output (MIMO) services at any of the frequencies described above. The systems described herein can support any combination of SISO and MIMO signals across various bands of frequency spectrum. In some example embodiments, the systems described herein may provide MIMO streams for WiMAX, LTE, and HSPA services while only providing SISO streams for other services. Other combinations of MIMO and SISO services are used in other embodiments.

Generally, the ability to switch from one layer to another within a particular protocol may afford more efficient use of bandwidth and can be applied to various radio access technologies having various layers, including radio link control (RLC) layers, medium access control (MAC) layers, and physical layers. LTE benefits substantially from a conversion from the physical layer to the MAC layer for transport through a DAS because the physical layer is much less efficient with bits than the MAC layer.

In exemplary embodiments, the medium access control (MAC) protocol data units (PDUs) are recovered by undoing the LTE physical layer processing (or other physical layer processing, such as another radio access technology's physical layer processing) done by the radio access network (RAN) interface (such as an eNodeB) and extracting just the LTE media access protocol (MAC) protocol data units (PDUs). In exemplary embodiments, this conversion to MAC PDUs and back essentially acts as a transport compression and transport decompression system.

FIGS. 1A-1Dare block diagrams of exemplary embodiments of distributed antenna systems100. Each ofFIGS. 1A-1Billustrates a different embodiment of a distributed antenna system100, labeled100A-100B respectively.

FIG. 1Ais a block diagram of an exemplary embodiment of a distributed antenna system100, distributed antenna system100A. Distributed antenna system100A includes a host unit102and at least one antenna unit104(including antenna unit104-1and any quantity of optional antenna units104through optional antenna unit104-A) communicatively coupled to the host unit102through at least one digital communication link106(including digital communication link106-1and any quantity of optional digital communication links106through optional digital communication link106-A). In exemplary embodiments, the at least one antenna unit104is remotely located from the host unit102.

The host unit102is communicatively coupled to at least one radio access network (RAN) interface108(including radio access network (RAN) interface108-1and any quantity of optional radio access network (RAN) interfaces108through optional radio access network (RAN) interface108-B). In the forward path, the host unit102is configured to receive wireless network information from each of the at least one radio access network (RAN) interface108. As described in more detail below, the host unit102is configured to convert wireless network information from each of the at least one radio access network (RAN) interface108into a more efficient format (such as to DAS MAC PDUs from baseband IQ pairs) for transport (either directly or through other components of the distributed antenna system100A) to the at least one antenna unit104across the at least one digital communication link106.

Similarly in the reverse path, in exemplary embodiments the host unit102is configured to receive uplink data streams formatted in a more efficient format (such as DAS MAC PDUs) across a respective digital communication link106from at least one antenna unit104. In exemplary embodiments, the host unit102is further configured to combine multiple received uplink data streams formatted in the more efficient format (such as DAS MAC PDUs) into a single aggregate uplink data stream formatted in the more efficient format (such as DAS MAC PDUs). In exemplary embodiments, the multiple received uplink data streams are combined using summation (either digital or analog), weighted summation, averaging, multiplexing, etc. The host unit102is further configured to convert the received uplink data stream (or the aggregate uplink data stream) formatted in the more efficient format (such as DAS MAC PDUs) to signals formatted for the associated radio access network (RAN) interface108(such as baseband IQ samples) and further configured to communicate the signals formatted for the associated radio access network (RAN) interface108to the associated radio access network (RAN) interface108.

Each antenna unit104is communicatively coupled to the host unit102across a digital communication link106. Specifically, antenna unit104-1is communicatively coupled to the host unit102across digital communication link106-1and optional antenna unit104-A is communicatively coupled to the host unit102across digital communication link106-A. In exemplary embodiments, some or all of the digital communication links106are wired digital communication links, such as fiber optic cabling, coaxial cabling, twisted pair cabling, etc. In exemplary embodiments, some or all of the digital communication links106are wireless digital communication links. In exemplary embodiments, a synchronous data stream using Ethernet PHY components is communicated across the digital communication links106, rather than packetized data, such as traditional Internet Protocol (IP) packets. In exemplary embodiments, the same hardware found in normal packetized Internet Protocol (IP) transport is used, it is just not wrapped into Internet Protocol (IP) packets. Each antenna unit104includes components for converting the wireless network information from the more efficient format (such as DAS MAC PDUs) for transport across the at least one digital communication link106to radio frequency, for transmission wirelessly using the at least one antenna110.

In the forward/downstream path, each antenna unit104is configured to convert at least one wireless network information from the more efficient format (such as DAS MAC PDUs) to a downlink radio frequency (RF) signal in a radio frequency band for transmission wirelessly using the at least one antenna110. In exemplary embodiments, this may include protocol layer processors, converters, and/or translators, digital to analog converters, and oscillators described in more detail below. Each antenna unit104is further configured to transmit the downlink radio frequency signal in the radio frequency band to at least one subscriber unit112(including subscriber unit112-1and any quantity of optional subscriber units112through optional subscriber unit112-D) using at least one antenna110. In exemplary embodiments, at least one antenna unit104-1is configured to transmit one downlink radio frequency signal to one subscriber unit112-1using an antenna110-1and another radio frequency signal to another subscriber unit112-D using another antenna110-C. In exemplary embodiments, other combinations of radio frequency antennas110and other components are used to communicate other combinations of radio frequency signals in other various radio frequency bands to various subscriber units112.

Similarly in the reverse/upstream path, in exemplary embodiments each antenna unit104is configured to receive an uplink radio frequency (RF) signal from at least one subscriber unit112using at least one antenna110. Each antenna unit104is further configured to convert the radio frequency signals to at least one uplink data stream. Each antenna unit104is further configured to convert wireless network information from the uplink radio frequency signals to a more efficient format (such as DAS MAC PDUs) for transmission across the at least one digital communication link106to the host unit102. In exemplary embodiments, this may include oscillators, digital to analog converters, and protocol layer converters and/or translators described in more detail below.

In exemplary embodiments, a master reference clock is distributed between the various components of the distributed antenna system100A to keep the various components locked to the same clock. In exemplary embodiments, the master reference clock is generated based on a signal received from the at least one radio access network interface108-1. In exemplary embodiments, the master reference clock is generated within another component of the distributed antenna system, such as an antenna unit104.

FIG. 1Bis a block diagram of an exemplary embodiment of a distributed antenna system100, distributed antenna system100B. Distributed antenna system100B includes a host unit102and at least one antenna unit104(including antenna unit104-1and any quantity of optional antenna units104through optional antenna unit104-A). Distributed antenna system100B includes similar components to distributed antenna system100A and operates according to similar principles and methods as distributed antenna system100A described above. The difference between distributed antenna system100B and distributed antenna system100A is that distributed antenna system100B includes a distributed switching network114. Distributed switching network114couples the host unit102with the at least one antenna unit104. Distributed switching network114may include one or more distributed antenna switches (such as a DAS expansion host and/or an Ethernet switch) or other intermediary components/nodes that functionally distribute downlink signals from the host unit102to the at least one antenna unit104. Distributed switching network114also functionally distributes uplink signals from the at least one antenna unit104to the host unit102. In exemplary embodiments, the distributed switching network114can be controlled by a separate controller or another component of the system. In exemplary embodiments the switching elements of the distributed switching network114are controlled either manually or automatically. In exemplary embodiments, the routes can be pre-determined and static. In other exemplary embodiments, the routes can dynamically change based on time of day, load, or other factors.

Each antenna unit104is communicatively coupled to the distributed switching network114across a digital communication link116. Specifically, antenna unit104-1is communicatively coupled to the distributed switching network114across digital communication link116-1and optional antenna unit104-A is communicatively coupled to the distributed switching network114across digital communication link116-A. In exemplary embodiments, some or all of the digital communication links116are wired digital communication links, such as fiber optic cabling, coaxial cabling, twisted pair cabling, etc. In exemplary embodiments, some or all of the digital communication links116are wireless digital communication links. In exemplary embodiments, each antenna unit104includes components configured for extracting at least one downlink data stream from an aggregate downlink data stream and components configured for aggregating at least one uplink data stream into an aggregate uplink data stream as well as at least one radio frequency converter configured to convert between at least one data stream and at least one radio frequency band and at least one antenna110configured to transmit and receive signals in the at least one radio frequency band to at least one subscriber unit112.

FIG. 1Cis a block diagram of an exemplary embodiment of a distributed antenna system100, distributed antenna system100C. Distributed antenna system100C includes at least one radio access network interface108(such as radio access network interface108-1and any quantity of optional radio access network interfaces108through optional radio access network interface108-B) and at least one antenna unit104(including antenna unit104-1and any quantity of optional antenna units104through optional antenna unit104-A). Distributed antenna system100C includes some components similar to components of distributed antenna system100A and operates according to similar principles and methods as distributed antenna system100A described above. The difference between distributed antenna system100C and distributed antenna system100A is that distributed antenna system100C does not include a host unit102and the at least one radio access network interface108transports using the more efficient format directly to the at least one antenna units104. The at least one radio access network interface108is communicatively coupled to the at least one antenna unit104. In exemplary embodiments, a single radio access network interface108is communicatively coupled to a plurality of antenna units104. In other exemplary embodiments, a plurality of radio access network interfaces108are communicatively coupled to a single antenna unit104.

In exemplary embodiments of the forward path, the at least one radio access network (RAN) interface108is configured to transport (either directly or through other components of the distributed antenna system100C) the more efficient format (such as DAS MAC PDUs) to the at least one antenna unit104across the at least one digital communication link106, rather than having a host unit102convert to the more efficient format (such as DAS MAC PDUs) from a less efficient format (such as baseband IQ pairs). Similarly in exemplary embodiments of the reverse path, the at least one radio access network (RAN) interface108is configured to receive (either directly or through other components of the distributed antenna system100C) the more efficient format (such as DAS MAC PDUs) from the at least one antenna unit104across the at least one digital communication link106, rather than having a host unit convert from the more efficient format (such as DAC MAC PDUs) to the less efficient format (such as baseband IQ pairs) in-between the radio access network interface108and the antenna unit104.

Each antenna unit104is communicatively coupled to the at least one radio access network interface108across a digital communication link106. Specifically, antenna unit104-1is communicatively coupled to the radio access network interface108-1across digital communication link106-1and optional antenna unit104-A is communicatively coupled to the radio access network interface108-B across digital communication link106-A. In exemplary embodiments, some or all of the digital communication links106are wired digital communication links, such as fiber optic cabling, coaxial cabling, twisted pair cabling, etc. In exemplary embodiments, some or all of the digital communication links106are wireless digital communication links. Each antenna unit104includes components for converting, in the forward path, the wireless network information from the more efficient format (such as DAS MAC PDUs) for transport across the at least one digital communication link106to radio frequency, for transmission wirelessly using the at least one antenna110. Each antenna unit104also includes components for converting, in the reverse path, the wireless network information from radio frequency received wirelessly using the at least one antenna110to the more efficient format (such as DAS MAC PDUs) for transport across the at least one digital communication link106to the at least one radio access network interface108.

FIG. 1Dis a block diagram of an exemplary embodiment of a distributed antenna system100, distributed antenna system100D. Distributed antenna system100D includes at least one radio access network interface108(including radio access network interface108-1and any quantity of optional radio access network interfaces108through optional radio access network interfaces108-B) and at least one antenna unit104(including antenna unit104-1and any quantity of optional antenna units104through optional antenna unit104-A). Distributed antenna system100D includes similar components to distributed antenna system100C and operates according to similar principles and methods as distributed antenna system100C described above. The difference between distributed antenna system100D and distributed antenna system100C is that distributed antenna system100D includes a distributed switching network114. Distributed switching network114couples the at least one radio access network interface108with the at least one antenna unit104. Distributed switching network114may include one or more distributed antenna switches (such as a DAS expansion unit and/or an Ethernet switch) or other intermediary components/nodes that functionally distribute downlink signals from the at least one radio access network interface108to the at least one antenna unit104. Distributed switching network114also functionally distributes uplink signals from the at least one antenna unit104to the at least one radio access network interface108. In exemplary embodiments, the distributed switching network114can be controlled by a separate controller or another component of the system. In exemplary embodiments the switching elements of the distributed switching network114are controlled either manually or automatically. In exemplary embodiments, the routes can be pre-determined and static. In other exemplary embodiments, the routes can dynamically change based on time of day, load, or other factors.

Each antenna unit104is communicatively coupled to the distributed switching network114across a digital communication link116. Specifically, antenna unit104-1is communicatively coupled to the distributed switching network114across digital communication link116-1and optional antenna unit104-A is communicatively coupled to the distributed switching network114across optional digital communication link116-A. In exemplary embodiments, some or all of the digital communication links116are wired digital communication links, such as fiber optic cabling, coaxial cabling, twisted pair cabling, etc. In exemplary embodiments, some or all of the digital communication links116are wireless digital communication links. In exemplary embodiments, each antenna unit104includes components configured for extracting at least one downlink data stream from an aggregate downlink data stream and components configured for aggregating at least one uplink data stream into an aggregate uplink data stream as well as at least one radio frequency converter configured to convert between at least one data stream and at least one radio frequency band and at least one antenna110configured to transmit and receive signals in the at least one radio frequency band to at least one subscriber unit112.

FIGS. 2A-2Bare block diagrams of exemplary embodiments of host unit102. Each ofFIGS. 2A-2Billustrates a different embodiment of a host unit102, labeled102A-102B respectively.

FIG. 2Ais a block diagram of an exemplary embodiment of a host unit102, host unit102A, used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. Exemplary host unit102A includes at least one host network interface202(including host network interface202-1and any quantity of optional host network interfaces202through optional host network interface202-B), at least one physical layer processor204(including physical layer processor204-1and any quantity of optional physical layer processors204through optional physical layer processor204-B), a distributed antenna system (DAS) medium access control (MAC) layer processor206, a distributed antenna system (DAS) transport physical layer processor208, an optional master host clock unit210, an optional processor212, optional memory214, and an optional power supply216. In exemplary embodiments, the at least one physical layer processor204is a radio access technology (RAT) physical layer processor, such as an LTE physical layer processor or another type of RAT physical layer processor. In exemplary embodiments, the DAS transport physical layer processor208is an Ethernet physical layer processor. In other embodiments, the DAS transport physical layer processor208is another type. In exemplary embodiments, the host network interfaces202, the physical layer processors204, the distributed antenna system medium access control layer processor206, the DAS transport physical layer processor208and/or master host clock unit210are implemented in whole or in part by optional processor212and memory214. In exemplary embodiments, power supply216provides power for the various components of the host unit102A. In exemplary embodiments, the physical layer processors204are LTE physical layer processors because the signals received from the corresponding host network interfaces202are LTE physical layer signals. In exemplary embodiments, some of the physical layer processors204are physical layer processors for radio access technologies other than LTE and the physical layer signals received from the corresponding host network interfaces202are for these other radio access technologies. In exemplary embodiments, no physical layer processors204are included with some corresponding host network interfaces202that receive signals that are not physical layer signals. In exemplary embodiments, combinations of LTE physical layer processors204, other radio access technology physical layer processors204, and no physical layer processors204are included in host unit102A. In exemplary embodiments, the host unit102provides/distributes power to at least a first of the at least one antenna unit104.

In the forward path, each host network interface202receives downlink wireless network information transported in another format from a respective radio access network interface108and converts the downlink wireless network information from the another format to the baseband downlink wireless network information type. In exemplary embodiments, the purpose of the host network interface202is to convert the data form the format used by the base station into a format acceptable to the RAT physical layer processor204. In exemplary embodiments, at least some of the host network interfaces202communicate using digital signals with the radio access network interfaces108. In exemplary embodiments, at least some of the host network interfaces202communicate using analog signals (such as radio frequency (RF) and/or intermediate frequency (IF) analog signals) with the radio access network interfaces108. In exemplary embodiments, a host network interface202is connected to an analog radio access network interface108, such as a small cell, and the host exchanges analog RF with the analog radio access network interface108and the host102A includes a digital front end (such as within the host network interface202or between the host network interface202and the RAT physical layer processor204) to convert between the RF and the stream of bits exchanged with the RAT physical layer processor204.

In specific implementations, at least one host network interface108receives Common Public Radio Interface (CPRI) signals from a CPRI interface of a base band unit acting as the radio access network interface108, converts the CPRI signals into a format compatible with the RAT physical layer processor. In one embodiment of a CPRI interface, the data is in an LTE PHY format and has already been coded, modulated, and fully processed according to the LTE PHY specifications. It is an I/Q stream coming from the radio access network interface108. The LTE PHY processor (RAT physical layer processor204-1) in the host unit102A would basically undo the LTE PHY processing that was done by the BBU (radio access network interface108). The LTE physical layer data (RAT physical layer data) is translated into the LTE MAC PDUs (RAT MAC PDUs) by the LTE PHY processor (RAT physical layer processor204). The DAS MAC (transport medium access control (MAC) processor206), which may be implemented as an FPGA, determines what to do with these LTE MAC PDUs (RAT MAC PDUs) including how to frame them, format them, and put them into their own structure that is required for transport over the digital communication medium106(such as Category building cable or other lower bandwidth cable).

In the reverse path, each host network interface202receives uplink wireless network information in the RAT physical format and converts them into a format for communication with the respective radio access network interface108. In specific implementations, at least one host network interface108receives uplink physical layer data signals and converts the uplink physical layer data signals into uplink CPRI signals and communicates the CPRI signals to the at least one radio access network interface108.

In the forward path, each physical layer processor204receives downlink physical layer data signals and converts the downlink physical layer data signals in the physical layer to downlink medium access control (MAC) layer protocol data units (PDUs) in the medium access control (MAC) layer, wherein the medium access control layer uses relevant bits more efficiently than the physical layer. In the reverse path, each physical layer processor204receives uplink RAT MAC layer protocol data units in the RAT MAC layer and converts the uplink RAT MAC layer PDUs to uplink physical layer data signals.

In exemplary embodiments, the physical layer processor204in the host unit102performs functions similar to a user equipment (UE) device in that it receives the RAT physical signals and reverses the physical processor performed by the radio access network. In the uplink the physical layer processor204in the host unit102creates an uplink physical signal representation of the wireless network information such that the radio access network to which the host unit102is connected through the radio access network interface108can perform its normal uplink processing. In exemplary embodiments, the DAS processing is transparent to the radio access network interface108and the radio access network generally as well as the user equipment (UE).

In the forward path, the DAS MAC layer processor206converts the downlink RAT MAC PDUs in the RAT MAC into downlink distributed antenna system (DAS) transport medium access control (MAC) layer protocol data units (PDUs) in a downlink distributed antenna system (DAS) transport medium access control (MAC) layer for transport through the distributed antenna system (DAS). In the reverse path, the DAS MAC layer processor206converts the uplink distributed antenna system (DAS) transport medium access control (MAC) layer protocol data units (PDUs) in an uplink distributed antenna system (DAS) transport medium access control (MAC) layer into uplink medium access control (MAC) layer protocol data units (PDUs) in the medium access control (MAC) layer. In exemplary embodiments, the DAS MAC layer processor206also broadcasts signals to a plurality of different remote antenna units104. In exemplary embodiments, the DAS MAC layer processor206also combines uplink DAS transport MAC layer PDUs from different antenna units104in an intelligent way. In exemplary embodiments, multiple received uplink data streams are combined using summation (either digital or analog), weighted summation, averaging, multiplexing, etc. In exemplary embodiments, combining in the upstream occurs by recovering the RAT MAC PDUs (such as LTE MAC PDUs) for all the signals to be combined and then having a plurality of RAT physical layer processors204(such as LTE PHY processors) individually process the signals from RAT MAC PDUs (such as LTE MAC PDUs) into I/Q samples, which are then digitally combined in a combiner that may be within a host network interface202or in between the RAT physical layer processors204and a host network interface202. In other embodiments, the DAS MAC PDUs from the multiple remote units104are combined bitwise by the DAS MAC processor206. In exemplary embodiments, the combining is done through majority logic and/or weighted combining. In exemplary embodiments, all the signals need to be synchronized so the host unit102A knows which bit goes with which bit and so the combining results in accurate data. In exemplary embodiments, the antenna units104are synchronized with the host unit102. In exemplary embodiments, the DAS MAC layer processor206determines whether multiple antenna units104received signals from a particular remote/subscriber unit112and whether there is valid data coming from multiple antenna units104. If there is valid data coming from multiple antenna units104, the DAS MAC layer processor206will combine the bits. Because there are RAT physical layer processors406(such as LTE PHY processors) at the antenna units104(described below), the RAT physical layer processors406at the antenna units104could generate quality measurements, such as a signal to noise ratio (SNR), modulation quality, etc. and then feedback the quality metrics to the host unit102A to use in weighing and combining of the signals.

In the forward path, the DAS transport physical layer processor208converts the downlink DAS transport MAC layer PDUs in the downlink DAS transport MAC layer into downlink DAS physical layer data streams in the DAS physical layer and communicates the downlink DAS physical layer data streams across the at least one digital communication medium106to the at least one antenna unit104. In the reverse path, the DAS transport physical layer processor208receives uplink DAS physical layer data streams in the DAS physical layer from the at least one digital communication medium106and converts the uplink DAS physical layer data streams into uplink DAS transport MAC layer PDUs in the uplink DAS transport MAC layer.

In exemplary embodiments, the antenna units104are synchronized with each other and/or the host unit102. In exemplary embodiments, the antenna units104and/or the host unit102are synchronized based on a clock signal propagated from the host unit102that is generated from a signal received by the host unit102from the radio access network interface108(such as a baseband unit BBU and/or small cell) so the network synchronization of the radio access network interface108(such as a baseband unit BBU and/or small cell) is propagated through to the various components of the distributed antenna system100. In exemplary embodiments, the master host clock unit210extracts the master reference clock from a signal supplied by at least one radio access network interface108. In exemplary embodiments, the master clock unit210distributes the master reference clock to other components of the distributed antenna system100in the downlink. In exemplary embodiments, the master host clock unit210distributes this master clock with other radio access network interfaces108through the corresponding host network interfaces202. In exemplary embodiments (such as those where the radio access network interface is an analog radio frequency interface), the master host clock unit210generates a master reference clock and distributes the generated master reference clock with radio access network interfaces108through the corresponding host network interfaces202.

FIG. 2Bis a block diagram of an exemplary embodiment of a host unit102, host unit102B, used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. Exemplary host unit102B includes at least one host network interface202(including host network interface202-1and any quantity of optional host network interfaces202through optional host network interface202-B), a distributed antenna system (DAS) medium access control (MAC) layer processor206, an DAS transport physical layer processor208, an optional master host clock unit210, an optional processor212, optional memory214, and an optional power supply216. In exemplary embodiments, the host network interfaces202, the DAS MAC layer processor206, the DAS transport physical layer processor208and/or master host clock unit210are implemented in whole or in part by optional processor212and memory214. In exemplary embodiments, power supply216provides power for the various components of the host unit102B. Host unit102B includes similar components to host unit102A and operates according to similar principles and methods as host unit102A described above.

The difference between host unit102B and host unit102A is that host unit102B does not include any RAT physical layer processors204. In exemplary embodiments, the LTE PHY processor (RAT physical layer processor204) is not necessary in the host unit102A because the host unit102A receives the LTE MAC PDUs (RAT MAC PDUs) directly from the baseband unit (BBU, such as radio access network interface108). In exemplary embodiments, this may require changes to the baseband unit (BBU, such as radio access network interface108) to allow output of the LTE MAC PDUs (RAT MAC PDUs) instead of the I/Q stream. In exemplary embodiments, the RAT physical layer processor204is not included and/or bypassed with some signals so that I/Q samples are transmitted through the distributed antenna system100instead of the MAC PDUs. In exemplary embodiments, this is useful with other radio access technologies (RAT) that do not require as much bandwidth for transport using I/Q baseband samples as LTE. Accordingly, I/Q samples could be packed into a DAS physical layer compatible frame. In exemplary embodiments, this enables data represented in IQ space to be transported directly instead of translating it into the MAC PDUs for transport. The benefit of this approach is that the distributed antenna system100can be radio access technology (RAT) agnostic. This could be more useful with less bandwidth hungry wireless access technology protocols, such as 2G and/or 3G radio access technologies (RAT). In exemplary embodiments, this approach is less complicated because it does not require the additional LTE PHY processors in both the host unit102and antenna units104. In exemplary embodiments, some signals go through a RAT physical layer processor204and are converted into MAC PDUs, while others remain as I/Q samples, but all the signals can be multiplexed together and transported through the distributed antenna system100. This enables inputs from different sources to be used while sharing a single cable. In exemplary embodiments, there is some framing within the payload with both MAC PDUs and synchronous I/Q samples.

Accordingly and in the forward path, the DAS MAC layer processor206converts the downlink RAT MAC data signals in the MAC layer into downlink distributed antenna system (DAS) transport medium access control (MAC) layer protocol data units (PDUs) in a downlink distributed antenna system (DAS) transport medium access control (MAC) layer for transport through the distributed antenna system (DAS). In the reverse path, the DAS MAC layer processor206converts the uplink distributed antenna system (DAS) transport medium access control (MAC) layer protocol data units (PDUs) in an uplink distributed antenna system (DAS) transport medium access control (MAC) layer into RAT MAC layer data signals in the MAC layer. This host unit102B could be used in exemplary embodiments where the radio access network interface108communicates RAT MAC PDUs directly with the host network interface202, so it is not necessary to perform any physical RAT layer processing to get the wireless network information into the more efficient format. This host unit102B could also be used in exemplary embodiments where it is not necessary to undo any physical RAT layer processing even though the signals received from the radio access network interface108have had physical RAT layer processing, because the physical RAT layer processing is efficient enough. In exemplary embodiments, combinations of host unit102A and host unit102B allow for some wireless network information to have the physical RAT layer processing undone using a physical layer processor and others to not have it undone, so a physical layer processor204is not necessary.

FIGS. 3A-3Jare block diagrams of exemplary embodiments of base station host network interfaces302used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. Each ofFIGS. 3A-3Jillustrates a different embodiment of a type of host network interface202, labeled104A-104D respectively.

FIG. 3Ais a block diagram of an exemplary embodiment of a host network interface202, general host network interface202A. General host network interface202A includes signal to data stream conversion module302A, network interface clock unit304A, optional processor306, optional memory308, and optional power supply310. In exemplary embodiments, signal to data stream conversion module302A is communicatively coupled to a radio access network interface output312A of a radio access network interface108A. Signal to data stream conversion module302A is also communicatively coupled to at least physical layer processor204. In exemplary embodiments, the signal to data stream conversion module302A and/or the network interface clock unit304A are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the host network interface202A.

In the downlink, signal to data stream conversion module302A is configured to receive downlink signals from the radio access network interface output312A of the radio access network interface108A. The signal to data stream conversion module302A is further configured to convert the received downlink signals to a downlink data stream. In the uplink, signal to data stream conversion module302A is configured to receive an uplink data stream from an physical layer processor204. The signal to data stream conversion module302A is further configured to convert the uplink data stream to uplink signals. Signal to data stream conversion module302A is further configured to communicate the uplink signals to the radio access network interface output312A of the radio access network interface108A.

In exemplary embodiments, the network interface clock unit304A is communicatively coupled to a radio access network interface clock unit314A of the radio access network interface108A. In exemplary embodiments, a master reference clock is provided from the radio access network interface clock unit314A of the radio access network interface108A to the network interface clock unit304A of the host network interface202A. In other exemplary embodiments, a master reference clock is provided to the radio access network interface clock unit314A of the radio access network interface108A from the network interface clock unit304A of the host network interface202A.

FIG. 3Bis a block diagram of an exemplary embodiment of a type of base station interface102, general host network interface202B. General host network interface202B includes signal to data stream conversion module302B, network interface clock unit304B, optional processor306, optional memory308, and optional power supply310. Similarly to general host network interface202A, signal to data stream conversion module302B is communicatively coupled to a radio access network interface output312B of a radio access network interface108B. In contrast to general host network interface202A, base station network interface clock unit304B is not coupled directly to radio access network interface clock unit314B of radio access network interface108B to provide the master reference clock to the network interface clock unit304B. Instead, radio access network interface clock unit314B provides the master reference clock to the radio access network interface output312B and the master reference clock is embedded in the downstream signal from the radio access network interface output312B to the signal to data stream conversion module302B of the host network interface202B, which then provides it to the network interface clock unit304B.

In exemplary embodiments where the master reference clock is provided from an radio access network interface108B to the distributed antenna system100, the master reference clock can be embedded in the downlink signals by the radio access network interface clock unit314B so that the downlink signals communicated from the radio access network interface output312B of the radio access network interface108B to the signal to data stream conversion module302B can be extracted by the network interface clock unit304B and distributed as appropriate within the host network interface202B and the distributed antenna system100generally. In exemplary embodiments, the signal to data stream conversion module302B and/or the network interface clock unit304B are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the host network interface202B.

FIG. 3Cis a block diagram of an exemplary embodiment of a type of host network interface202, baseband host network interface202C. Baseband host network interface202C includes a baseband to data stream conversion module302C, a baseband network interface clock unit304C, an optional processor306, optional memory308, and an optional power supply310. In exemplary embodiments, baseband to data stream conversion module302C is communicatively coupled to a baseband base station output312C of a radio access network interface that is a baseband base station108C. Baseband to data stream conversion module302C is also communicatively coupled to at least one physical layer processor204. In exemplary embodiments, the baseband to data stream conversion module302C and/or the baseband network interface clock unit304C are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the baseband host network interface202C.

In the downlink, baseband to data stream conversion module302C is configured to receive baseband mobile wireless access signals (such as I/Q data) from a baseband base station output312C of a baseband base station108C. The baseband to data stream conversion module302C is further configured to convert the received baseband mobile wireless access signals to a downlink data stream. In the uplink, baseband to data stream conversion module302C is configured to receive a data stream from physical layer processor204. The baseband to data stream conversion module302C is further configured to convert the uplink data stream to uplink baseband wireless access signals. Baseband to data stream conversion module302C is further configured to communicate the uplink baseband wireless access signals to the baseband base station output312C.

In exemplary embodiments, the baseband network interface clock unit304C is communicatively coupled to a baseband base station clock unit314C of the baseband base station108C. In exemplary embodiments, a master reference clock is provided from the baseband base station clock unit314C of the baseband base station108C to the baseband network interface clock unit304C of the baseband host network interface202C. In exemplary embodiments, a master reference clock is provided to the baseband base station clock unit314C of the baseband base station108C from the baseband network interface clock unit304C of the baseband host network interface202C.

FIG. 3Dis a block diagram of an exemplary embodiment of a type of base station interface102, baseband network interface202D. Baseband network interface202D includes a baseband to data stream conversion module302D, a baseband network interface clock unit304D, an optional processor306, optional memory308, and an optional power supply310. Similarly to baseband host network interface202C, baseband to data stream conversion module302D is communicatively coupled to a baseband base station output312D of a radio access network interface that is a baseband base station108D and to at least one physical layer processor204. In contrast to baseband host network interface202C, baseband network interface clock unit304D is not coupled directly to baseband base station clock unit314D of baseband base station108D to provide and/or receive the master reference clock to/from the baseband base station108D. Instead, baseband base station output312D provides the master reference clock to the baseband to data stream conversion module302D and the master reference clock is embedded in downstream signals from the baseband base station output312D of baseband base station108D to the baseband to data stream conversion module302D of the baseband network interface202D.

In exemplary embodiments where the master reference clock is provided from the baseband base station108D to the distributed antenna system, the master reference clock can be embedded in the downlink signals by the baseband base station clock unit314D so that the downlink signals communicated from the baseband base station output312D of the baseband base station108D to the baseband to data stream conversion module302D can be extracted by the baseband network interface clock unit304D and distributed as appropriate within the baseband network interface202D and the distributed antenna system generally. In exemplary embodiments, the baseband to data stream conversion module302D and/or the baseband network interface clock unit304D are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the baseband network interface202D.

FIG. 3Eis a block diagram of an exemplary embodiment of a type of host network interface202, Common Public Radio Interface (CPRI) host network interface202E. CPRI host network interface202E includes a CPRI to data stream conversion module302E, a CPRI network interface clock unit304E, an optional processor306, optional memory308, and an optional power supply310. In exemplary embodiments, CPRI to data stream conversion module302E is communicatively coupled to a CPRI base station output312E of a host network interface202that is a CPRI base station108E. CPRI to data stream conversion module302E is also communicatively coupled to at least one physical layer processor204. In exemplary embodiments, the CPRI to data stream conversion module302E and/or the CPRI network interface clock unit304E are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the CPRI host network interface202E.

In the downlink, CPRI to data stream conversion module302E is configured to receive CPRI signals from the CPRI base station output312E. The CPRI to data stream conversion module302E is further configured to convert the received CPRI signals to a downlink data stream. In the uplink, CPRI to data stream conversion module302G is configured to receive a data stream from physical layer processor204. The CPRI to data stream conversion module302E is further configured to convert the uplink data stream to uplink CPRI signals. CPRI to data stream conversion module302E is further configured to communicate the uplink CPRI signal to the CPRI base station output312E.

In exemplary embodiments, the CPRI network interface clock unit304E is communicatively coupled to a CPRI base station clock unit314E of the CPRI base station108E. In exemplary embodiments, a master reference clock is provided from the CPRI base station clock unit314E of the CPRI base station108E to the CPRI network interface clock unit304C of the CPRI host network interface202E. In other exemplary embodiments, a master reference clock is provided to the CPRI base station clock unit314E of the CPRI base station108E from the CPRI network interface clock unit304E of the CPRI host network interface202E.

FIG. 3Fis a block diagram of an exemplary embodiment of a type of base station interface102, CPRI host network interface202F. CPRI host network interface202F includes a CPRI to data stream conversion module302F, a CPRI network interface clock unit304F, an optional processor306, optional memory308, and an optional power supply310. Similarly to CPRI host network interface202E, CPRI to data stream conversion module302F is communicatively coupled to a CPRI base station output312F of a radio access network interface108that is a CPRI base station108F and to at least one physical layer processor204. In contrast to CPRI host network interface202E, CPRI network interface clock unit304F is not coupled directly to CPRI base station clock unit314E of CPRI base station108F to provide and/or receive the master reference clock to/from the CPRI base station108F. Instead, CPRI to data stream conversion module302F provides the master reference clock to the CPRI host network interface202F and the master reference clock is embedded in downstream signals from the CPRI base station output312F of the CPRI base station108F to the CPRI to data stream conversion module302F of CPRI network interface202F.

In exemplary embodiments where the master reference clock is provided from the CPRI base station108F to the distributed antenna system100, the master reference clock can be embedded in the downlink signals by the CPRI base station clock unit314F so that the downlink signals communicated from the CPRI base station output312F of the CPRI base station108F to the CPRI to data stream conversion module302F can be extracted by the CPRI network interface clock unit304F and distributed as appropriate within the CPRI host network interface202F and the distributed antenna system100generally. In exemplary embodiments, the CPRI to data stream conversion module302F and/or the CPRI network interface clock unit304F are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the CPRI host network interface202F.

FIG. 3Gis a block diagram of an exemplary embodiment of a type of host network interface202, radio frequency (RF) host network interface202G. Radio frequency host network interface202G includes a radio frequency (RF) to data stream conversion module302G, a radio frequency (RF) network interface clock unit304G, an optional processor306, optional memory308, and an optional power supply310. In exemplary embodiments, radio frequency (RF) to data stream conversion module302G is communicatively coupled to a radio frequency (RF) base station output312G of a radio access network interface that is a radio frequency base station108G. Radio frequency to data stream conversion module302G is also communicatively coupled to at least one physical layer processor204. In exemplary embodiments, the radio frequency to data stream conversion module302G and/or the radio frequency network interface clock unit304G are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the radio frequency host network interface202G.

In the downlink, radio frequency to data stream conversion module302G is configured to receive radio frequency signals from the radio frequency base station output312G of the radio frequency base station108G. The radio frequency to data stream conversion module302G is further configured to convert the received radio frequency signals to a downlink data stream. In exemplary embodiments, this is done using oscillators and mixers. In the uplink, radio frequency to data stream conversion module302G is configured to receive a data stream from physical layer processor204. The radio frequency to data stream conversion module is further configured to convert the uplink data stream to radio frequency signals. In exemplary embodiments, this is done using oscillators and mixers. Radio frequency to data stream conversion module302G is further configured to communicate the uplink radio frequency signals to the radio frequency base station output312G of the radio frequency base station108G.

In exemplary embodiments, the radio frequency network interface clock unit304G is communicatively coupled to a radio frequency base station clock unit314G of the radio frequency base station108G. In exemplary embodiments, a master reference clock is provided from the radio frequency base station clock unit314G of the radio frequency base station108G to the radio frequency network interface clock unit304G of the radio frequency host network interface202G. In other exemplary embodiments, a master reference clock is provided to the radio frequency base station clock unit314G of the radio frequency base station108G from the radio frequency network interface clock unit304G of the host network interface202G.

FIG. 3His a block diagram of an exemplary embodiment of a type of base station interface102, radio frequency (RF) host network interface202H. Radio frequency host network interface202H includes a radio frequency (RF) to data stream conversion module202H, a radio frequency (RF) network interface clock unit204H, an optional processor306, optional memory308, and an optional power supply310. Similarly to radio frequency host network interface202G, radio frequency (RF) to data stream conversion module202H is communicatively coupled to a radio frequency (RF) base station output212H of a radio access network interface108that is a radio frequency base station108H and to at least one physical layer processor204. In contrast to radio frequency host network interface202G, radio frequency network interface clock unit204H is not coupled directly to radio frequency base station clock unit214H of radio frequency base station108H to provide and/or receive the master reference clock to/from the radio frequency base station108H. Instead, radio frequency to data stream conversion module202H provides the master reference clock to the radio frequency network interface clock unit304G and the master reference clock is embedded in downstream signals from the RF base station output312H of the RF base station108H to the RF to data stream conversion module302H of the RF network interface202H.

In exemplary embodiments where the master reference clock is provided from the radio frequency base station108H to the distributed antenna system, the master reference clock can be embedded in the downlink signals by the radio frequency base station clock unit214H so that the downlink signals communicated from the radio frequency base station output212H of the radio frequency base station108H to the radio frequency to data stream conversion module202H can be extracted by the radio frequency network interface clock unit204H and distributed as appropriate within the radio frequency host network interface202H and the distributed antenna system100generally. In exemplary embodiments, the radio frequency to data stream conversion module202H and/or the radio frequency network interface clock unit204H are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the host network interface202H.

FIG. 3Iis a block diagram of an exemplary embodiment of a type of host network interface202, Ethernet network interface202I. Ethernet network interface202I includes an Ethernet to data stream conversion module302I, an Ethernet network interface clock unit304I, an optional processor306, optional memory308, and an optional power supply310. In exemplary embodiments, Ethernet to data stream conversion module302I is communicatively coupled to an Ethernet output312I of an external device that is an Ethernet adapter108I to an internet protocol (IP) based network. Ethernet to data stream conversion module302I is also communicatively coupled to at least one physical layer processor204. In exemplary embodiments, the Ethernet to data stream conversion module302I and/or the Ethernet network interface clock unit304I are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the Ethernet network interface202I.

In the downlink Ethernet to data stream conversion module302I is configured to receive internet protocol packets from the Ethernet output312I. The Ethernet to data stream conversion module302I is further configured to convert the internet protocol packets to a downlink data stream. In the uplink, Ethernet to data stream conversion module302I is configured to receive a data stream from physical layer processor204. The Ethernet to data stream conversion module302I is further configured to convert the uplink data stream to uplink Ethernet frames. Ethernet to data stream conversion module302I is further configured to communicate the uplink Ethernet frames to the Ethernet output304I.

In exemplary embodiments, the Ethernet network interface clock unit304I is communicatively coupled to an Ethernet adapter clock unit314I of the Ethernet adapter108I. In exemplary embodiments, a master reference clock is provided from the Ethernet adapter clock unit314I of the Ethernet adapter108I to the Ethernet network interface clock unit304I of the Ethernet network interface202I. In other exemplary embodiments, a master reference clock is provided to the Ethernet adapter clock unit314I of the Ethernet adapter108I from the Ethernet network interface clock unit304I of the Ethernet network interface202I.

FIG. 3Jis a block diagram of an exemplary embodiment of a type of base station interface102, an Ethernet network interface202J. Ethernet network interface202J includes an Ethernet to data stream conversion module302J, an Ethernet network interface clock unit304J, an optional processor306, optional memory308, and an optional power supply310. Similarly to Ethernet network interface202I, Ethernet to data stream conversion module302J is communicatively coupled to an Ethernet output312J of an external device that is an Ethernet adapter108J and to at least one physical layer processor204. In contrast to Ethernet network interface202I, Ethernet network interface clock unit304J is not coupled directly to Ethernet adapter clock unit314J of Ethernet adapter108J to provide and/or receive the master reference clock to/from the Ethernet adapter108J. Instead, Ethernet output312J provides the master reference clock to the Ethernet to data stream conversion module302J and the master reference clock is embedded in downstream signals from the Ethernet output312J of the Ethernet adapter108J to the Ethernet to data stream conversion module302J of the Ethernet network interface202J.

In exemplary embodiments where the master reference clock is provided from the Ethernet adapter108J to the distributed antenna system100, the master reference clock can be embedded in the downlink signals by the Ethernet adapter clock unit314J so that the downlink signals communicated from the Ethernet output312J of the Ethernet adapter108J to the Ethernet to data stream conversion module302J can be extracted by the Ethernet network interface clock unit304J and distributed as appropriate within the Ethernet network interface202J and the distributed antenna system100generally. In exemplary embodiments, the Ethernet to data stream conversion module302J and/or the Ethernet network interface clock unit304J are implemented using optional processor306and optional memory308. In exemplary embodiments, the optional power supply310provides power to the various elements of the Ethernet network interface202J.

FIGS. 4A-4Bare block diagrams of exemplary embodiments of antenna unit104. Each ofFIGS. 4A-4Billustrates a different embodiment of a remote unit104, labeled104A-104B respectively.

FIG. 4Ais a block diagram of an exemplary embodiment of a remote unit104, remote unit104A, used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. The antenna unit104includes a distributed antenna system (DAS) transport physical layer processor402, a distributed antenna system (DAS) medium access control (MAC) layer processor404, a radio access technology (RAT) physical layer processor406, a radio frequency (RF) conversion module408, optional antenna unit clock unit410, optional processor412, optional memory414, and optional power supply416. In exemplary embodiments, the distributed antenna system (DAS) transport physical layer processor402is replaced with another type of Layer 1 (L1) processor for a transport Layer 1. In exemplary embodiments, the DAS transport physical layer processor402is an Ethernet physical layer processor. In other embodiments, the DAS transport physical layer processor402is another type. In exemplary embodiments, the distributed antenna system (DAS) medium access control (MAC) layer processor404is replaced with another type of Layer 2 (L2) processor for a transport Layer 2. In exemplary embodiments, the radio access technology (RAT) physical layer processor406is replaced with another type of Layer 1 (L1) processor for a radio access technology (RAT) Layer 1. In exemplary embodiments, DAS transport physical layer processor402, distributed antenna system medium access control layer processor404, RAT physical layer processor406, and/or radio frequency conversion module408are implemented at least in part by optional processor412and memory414. In exemplary embodiments, power for the antenna unit is provided by the host unit102remotely across a medium and the optional power supply416derives and/or extracts power from the medium. In exemplary embodiments, optional power supply416is used to power the various components of the antenna unit104.

In exemplary embodiments, the DAS transport physical layer processor402is configured to receive a downlink physical layer data stream from the host unit102across the digital communication link106and converts the downlink physical layer data stream in the physical layer to downlink distributed antenna system (DAS) transport medium access control (MAC) layer protocol data units (PDU). In exemplary embodiments, the DAS transport physical layer processor402is an Ethernet PHY that essentially undoes the processing of the corresponding DAS transport physical layer processor208in the host unit102. In exemplary embodiments, more input lines are included in the antenna unit104A. In exemplary embodiments, the distributed antenna system (DAS) medium access control (MAC) layer processor404is configured to convert the downlink distributed antenna system transport medium access control layer protocol data units in the downlink distributed antenna system transport medium access control layer into downlink medium access control layer protocol data units in the medium access control layer.

In exemplary embodiments, the RAT physical layer processor406is configured to generate a downlink RAT signal from the downlink medium access control layer protocol data units in the medium access control layer. In exemplary embodiments, the RF conversion module404converts the baseband downlink RAT signal to radio frequency signals for transmission at antenna110. In exemplary embodiments, the RAT physical layer processors406are LTE physical layer processors because the signals communicated with the RF conversion module404need to be LTE physical layer signals. In these embodiments, the LTE physical layer processors process OFDM in the downlink and SC-FDMA in the uplink. In exemplary embodiments, the LTE physical layer processor (RAT physical layer processor406) in the remote antenna unit104A doesn't perform the upper layer processing (L2/L3) in the protocol stack, rather it only performs the Layer 1 processing up to the creation of the MAC layer data.

In exemplary embodiments, some of the RAT physical layer processors406are physical layer processors for radio access technologies other than LTE and the physical layer signals received from the corresponding host network interfaces202are for these other radio access technologies. In exemplary embodiments, no RAT physical layer processors406are included when the RAT physical layer data is transported in some format from the host102to the antenna unit104A. In exemplary embodiments, combinations of LTE physical layer processors406, other RAT physical layer processors406, and no RAT physical layer processors406are included in antenna unit104A.

In exemplary embodiments, the RF conversion module408receives signals from antenna110and converts radio frequency signals to a baseband uplink RAT signal. In exemplary embodiments, the RAT physical layer processor406is configured to receive the baseband uplink RAT signal from the RF conversion module408and to generate uplink medium access control layer protocol data units in the medium access control layer from the baseband uplink RAT signal. In exemplary embodiments, the distributed antenna system (DAS) medium access control (MAC) layer processor404is configured to convert the uplink medium access control layer protocol data units in the medium access control layer into uplink distributed antenna system transport medium access control layer protocol data units in the uplink distributed antenna system transport medium access control layer. In exemplary embodiments, the DAS transport physical layer processor402is configured to convert the uplink distributed antenna system transport medium access control layer protocol data units to an uplink physical layer DAS data stream and to communicate the uplink physical layer DAS data stream to the host unit102across the digital communication link106.

FIG. 4Bis a block diagram of an exemplary embodiment of a remote unit104, remote unit104B, used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. The antenna unit104B includes an DAS transport physical layer processor402, a distributed antenna system (DAS) medium access control (MAC) layer processor404, a plurality of radio access technology (RAT) physical layer processors406(including RAT physical layer processor406-1, RAT physical layer processor406-2, and any quantity of optional RAT physical layer processors406through optional RAT physical layer processor406-G), a plurality of radio frequency (RF) conversion modules408, optional antenna unit clock unit410, optional processor412, optional memory414, and optional power supply416. In exemplary embodiments, DAS transport physical layer processor402, distributed antenna system medium access control layer processor404, RAT physical layer processor406, and/or radio frequency conversion module408are implemented at least in part by optional processor412and memory414. In exemplary embodiments, optional power supply416is used to power the various components of the antenna unit104. Antenna unit104B includes similar components to antenna unit104A and operates according to similar principles and methods as antenna unit104A described above.

The differences between antenna unit104A and antenna unit104B is that antenna unit104B includes a plurality of radio access technology (RAT) physical layer processors406(such as RAT physical layer processor406-1through optional RAT physical layer processor406-G), a plurality of RF conversion modules408(such as RF conversion module408-1through RF conversion module408-C), and optional Ethernet interface420. In exemplary embodiments, each of the radio access technology (RAT) physical layer processors406is replaced with another type of Layer 1 (L1) processors for a radio access technology (RAT) Layer 1. In exemplary embodiments, the DAS MAC layer processor404includes multiplexing functionality enabling multiple different signals to be received and multiplexed in different ways. In exemplary embodiments, such as MIMO applications or multi-signal applications, the DAS MAC layer processor404multiplexes the data for the different signals onto the same DAS transport physical layer processor402for transport across the digital communication link106to the host unit102. In exemplary embodiments, the DAS MAC layer processor404receives a plurality of uplink data streams from a plurality of RF conversion modules408. In exemplary embodiments, the DAS MAC layer processor404aggregates at least one uplink data stream received from an RF conversion module408-1with another uplink data stream received from another RF conversion module408-2. In exemplary embodiments, the DAS MAC layer processor404aggregates a plurality of uplink data streams into an aggregate uplink data stream that is transmitted through the DAS transport physical layer processor402.

In exemplary embodiments, more than one RAT physical layer processor406is communicatively coupled to a single RF conversion module408. For example, both optional RAT physical layer processor406-3and optional RAT physical layer processor406-4being communicatively coupled to single RF conversion module408-3. In these embodiments, more than one RAT physical layer data steam is communicated to a single RF conversion module. In exemplary embodiments, the RAT physical layer data stream from a plurality of RAT physical layer processors406are in the same band of operation (such as two different two different LTE signals, an LTE signal and a UMTS signal, etc.), such that they can be converted simultaneously by a single RF conversion module408. In exemplary embodiments, the two different signals from the two different RAT physical layer data streams are combined digitally at baseband and upconverted simultaneously using RF conversion module408using a single power amplifier.

In exemplary embodiments, the optional Ethernet interface408receives a downlink data stream from the DAS MAC layer processor404and converts it to Ethernet packets and communicates the Ethernet packets with an internet protocol network device. The optional Ethernet interface408also receives Ethernet packets from the internet protocol network device and converts them to an uplink data stream and communicates it to the DAS MAC layer processor404. In exemplary embodiments, the DAS MAC layer processor404also multiplexes the uplink data stream from the Ethernet packets with the uplink data streams from the RF conversion modules408. The optional Ethernet interface408is an example of how the additional bandwidth freed up through the methods described herein can be used to allow for additional services, such as an Ethernet pipe from the host unit102to at least one antenna unit104.

In exemplary embodiments, the optional antenna unit clock unit410extracts the master reference clock from the downlink data stream and uses this master clock within the antenna unit104to establish a common time base in the antenna unit104with the rest of the distributed antenna system100. In exemplary embodiments, the optional antenna unit clock unit410generates a master reference clock and distributes the generated master reference clock to other components of the distributed antenna system100(and even the radio access network interfaces108) in the upstream using the uplink data stream.

FIGS. 5A-5Care block diagrams of exemplary embodiments of RF conversion modules404used in antenna units of distributed antenna systems, such as the exemplary antenna unit100described above. Each ofFIGS. 5A-5Care block diagrams of exemplary embodiments of RF conversion module404, labeled RF conversion module404A-404D respectively.

FIG. 5Ais a block diagram of an exemplary RF conversion module404A including an optional data stream conditioner502, an RF frequency converter504, an optional RF conditioner506, and an RF duplexer508coupled to a single antenna110.

The optional data stream conditioner502is communicatively coupled to a RAT physical layer processor406and the radio frequency (RF) converter504. In the forward path, the optional data stream conditioner502conditions the downlink data stream (for example, through amplification, attenuation, and filtering) received from the RAT physical layer processor406and passes the downlink data stream to the RF converter504. In the reverse path, the optional data stream conditioner502conditions the uplink data stream (for example, through amplification, attenuation, and filtering) received from the RF converter504and passes the uplink data stream to the RAT physical layer processor406.

The RF converter504is communicatively coupled to the physical layer processor or the optional data stream conditioner502on one side and to either RF duplexer508or the optional RF conditioner506on the other side. In exemplary embodiments, the main function of the RF converter504is to convert between digital bits and radio frequency. In exemplary embodiments, the RF converter includes analog to digital converters, digital to analog converters, as well as mixers and local oscillators. In the downstream, the RF converter504converts a downlink data stream to downlink radio frequency (RF) signals and passes the downlink RF signals onto either the RF duplexer508or the optional RF conditioner506. In the upstream, the RF converter504converts uplink radio frequency (RF) signals received from either the RF duplexer508or the optional RF conditioner506to an uplink data stream and passes the uplink data stream to the RAT physical layer processor406or the optional data stream conditioner502.

The RF duplexer508is communicatively coupled to either the RF frequency converter504or the optional RF conditioner506on one side and the antenna110on the other side. The RF duplexer508duplexes the downlink RF signals with the uplink RF signals for transmission/reception using the antenna110.

FIG. 5Bis a block diagram of an exemplary RF conversion module404B including an optional data stream conditioner502, an RF frequency converter504, and an optional RF conditioner506coupled to a downlink antenna110A and an uplink antenna110B. RF conversion module404B includes similar components to RF conversion module404A and operates according to similar principles and methods as RF conversion module404A described above. The difference between RF conversion module404B and RF conversion module404A is that RF conversion module404B does not include RF duplexer508and instead includes separate downlink antenna110A used to transmit RF signals to at least one subscriber unit and uplink antenna110B used to receive RF signals from at least one subscriber unit.

FIG. 5Cis a block diagram of an exemplary RF conversion module404C that communicates downstream and upstream signals using a single antenna110through a TDD switch510(or other circulator). The RF conversion module404D includes an optional data stream conditioner502, an RF frequency converter504, an optional RF conditioner506, and the TDD switch510that is communicatively coupled to antenna110. RF conversion module404C operates according to similar principles and methods as RF conversion module404A described above. The difference between RF conversion module404C and RF conversion module404A is that RF conversion module404C uses the TDD switch510to switch between a downstream and upstream signal path using a single antenna110through TDD switch510. The TDD switch switches between the duplexed downlink and uplink signals for RF conversion module404C for transmission/reception using the single antenna110.

FIG. 5Dis a block diagram of an exemplary RF conversion module404D-1and exemplary RF conversion module404D-2that share a single antenna110through an RF diplexer512. The RF conversion module404D-1includes an optional data stream conditioner502-1, an RF frequency converter504-1, an optional RF conditioner506-1, and an RF duplexer508-1communicatively coupled to RF diplexer512that is communicatively coupled to antenna110. Similarly, the RF conversion module404D-2includes an optional data stream conditioner502-2, an RF frequency converter504-2, an optional RF conditioner506-2, and an RF duplexer508-2communicatively coupled to RF diplexer512that is communicatively coupled to antenna110. Each of RF conversion module404D-1and404D-2operate according to similar principles and methods as RF conversion module404A described above. The difference between RF conversion modules404D-1and404D-2and RF conversion module404A is that RF conversion modules404D-1and404D-2are both coupled to a single antenna110through RF diplexer512. The RF diplexer512diplexes the duplexed downlink and uplink signals for both RF conversion module404D-1and404D-2for transmission/reception using the single antenna110.

FIG. 6is a block diagram of an exemplary embodiment of a radio access (RAN) network interface108, radio access network interface108C, used in distributed antenna systems, such as the exemplary distributed antenna systems100described above. In exemplary embodiments, exemplary radio access network interface108C is a baseband unit (BBU) such as an LTE BBU that has been optimized to more efficiently communicate with remote units104in distributed antennas systems100. Exemplary radio access network interface108C includes at least one core network interface602(including core network interface602-1and any quantity of optional core network interfaces202through optional core network interface602-B), at least one Layer 2 (L2)/Layer 3 (L3) processor604(including L2/L3 processor604-1and any quantity of optional L2/L3 processors604through optional L2/L3 processor604-B), a transport medium access control (MAC) layer processor606(such as a distributed antenna system (DAS) MAC layer processor), a transport physical layer processor608(such as a distributed antenna system (DAS) physical layer processor), an optional radio access network interface clock unit610, an optional processor612, optional memory614, and an optional power supply616. In exemplary embodiments, the at least one core network interface602is replaced with another type of Layer 1 (L1) and Layer 2 (L2) processor for a core network Layer 1 (L1) and Layer 2 (L2). In exemplary embodiments, the at least one L2/L3 processor604is replaced with another type of Layer 2 (L2) and Layer 3 (L3) processor for a radio access technology (RAT) Layer 2 (L2) and Layer 3 (L3). In exemplary embodiments, the at least one L2/L3 processor604is an LTE L2/L3 processor. In exemplary embodiments, the transport MAC layer processor606is replaced with another type of Layer 2 processor for a transport Layer 2. In exemplary embodiments, the transport physical layer processor608is a transport Layer 1 processor for a transport Layer 1. In exemplary embodiments, the transport physical layer processor608is an Ethernet physical layer processor. In other embodiments, the transport physical layer processor608is another type of physical layer processor for transport through the distributed antenna system.

In exemplary embodiments, the core network interfaces602, the L2/L3 processors604, the transport MAC layer processor606, the transport physical layer processor608and/or optional radio access network interface clock unit610are implemented in whole or in part by optional processor612and memory614. In exemplary embodiments, power supply616provides power for the various components of the radio access network interface108C. In exemplary embodiments, the L2/L3 processors604are LTE L2/L3 processors because the signals received from the corresponding core network interfaces602are LTE core network signals, communicated using Internet Protocol (IP) over Gigabit Ethernet. In exemplary embodiments, some of the L2/L3 processors604are L2/L3 processors for radio access technologies (RAT) other than LTE and the signals received from the corresponding core network interfaces602are for these other radio access technologies (RAT). In exemplary embodiments, combinations of LTE L2/L3 processors604and other radio access technology L2/L3 processors604are included in radio access network interface108C. In exemplary embodiments, the radio access network interface108C provides/distributes power to at least a first of the at least one antenna unit104.

In the forward path, each core network interface602receives downlink physical layer core network signals and converts the downlink physical layer core network signals into downlink L2/L3 core network signals that are communicated to a respective L2/L3 processor604. In exemplary embodiments, the purpose of the core network interface602is to convert the data from the physical layer format used by the core network622into a format acceptable to the RAT L2/L3 processor604. In specific implementations, at least one core network interface602receives IP core network signals for LTE wireless signals from a core network622, converts the IP core network signals into a format compatible with the LTE L2/L3 processor604, such as packet data convergence protocol (PDCP) protocol data units (PDUs). In the reverse path, each core network interface602receives uplink wireless network information from the L2/L3 processor604and converts them into a format for communication with the respective core network622. In specific implementations, at least one core network interface602receives uplink L2/L3 data signals, such as PDCP PDUs and converts them into uplink physical layer IP core network signals and communicates the core network signals to the at least one additional component in the core network622.

In the forward path, each L2/L3 processor604receives the L2/L3 RAT signals and converts them into downlink radio access technology (RAT) medium access control (MAC) layer protocol data units (PDUs) in the radio access technology (RAT) medium access control (MAC) layer, wherein the radio access technology (RAT) medium access control layer uses relevant bits more efficiently than the radio access technology (RAT) physical layer (such as I/Q modulated LTE samples or other I/Q modulated samples). In the reverse path, each L2/L3 processor604receives uplink radio access technology (RAT) medium access control (MAC) layer protocol data units (PDUs) in the radio access technology (RAT) medium access control (MAC) layer and converts the uplink RAT MAC PDUs in the RAT MAC layer into L2/L3 core network signals.

In the forward path, the transport MAC layer processor606converts the downlink RAT MAC PDUs into downlink transport medium access control (MAC) layer protocol data units (PDUs) in a downlink transport medium access control (MAC) layer for transport to the at least one remote antenna unit104(such as through a distributed antenna system (DAS)). In the reverse path, the transport MAC layer processor606converts the uplink transport medium access control (MAC) layer protocol data units (PDUs) in an uplink transport medium access control (MAC) layer into the uplink radio access technology (RAT) medium access control (MAC) layer protocol data units (PDUs). In exemplary embodiments, the transport MAC layer processor606also broadcasts signals to a plurality of different remote antenna units104. In exemplary embodiments, the transport MAC layer processor606also combines uplink DAS transport MAC layer PDUs from different antenna units104in an intelligent way.

In the forward path, the transport physical layer processor608converts the downlink transport MAC layer PDUs in the downlink transport MAC layer into downlink transport physical layer data streams in the transport physical layer (such as an Ethernet physical layer or another DAS transport physical layer) and communicates the downlink transport physical layer data streams across the at least one digital communication medium106to the at least one antenna unit104. In the reverse path, the transport physical layer processor608receives uplink transport physical layer data streams in the transport physical layer (such as an Ethernet physical layer or another DAS transport physical layer) from the at least one digital communication medium106and converts the uplink transport physical layer data streams into uplink transport MAC layer PDUs in the uplink transport MAC layer. In exemplary embodiments, the transport physical layer processor608combines uplink transport physical layer data streams from different antenna units104in an intelligent way.

In exemplary embodiments, the radio access network interface clock unit610generates a master reference clock and distributes the generated master reference clock with the at least one remote antenna unit104and/or other components within the distributed antenna system100. In exemplary embodiments, the radio access network interface clock unit610communicates the master reference clock across a separate clock signal link620. In other exemplary embodiments, the radio access network interface clock unit610communicates the master reference clock through the transport physical layer processor608. In exemplary embodiments, the radio access network interface108C receives a master reference clock signal from at least one other component within the distributed antenna system100, such as the at least one remote antenna unit104or from another external source, such as a source provided from the core network620. In exemplary embodiments, the master reference clock is derived from a core network signal received by the at least one core network interface602.

FIG. 7is a flow diagram illustrating one exemplary embodiment of a method700for efficiently transporting wireless network information through a distributed antenna system. Exemplary method700begins at block702with converting downlink wireless network information received from a radio access network interface from a first protocol layer to a second protocol layer at a host unit in a distributed antenna system, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer. Exemplary method700proceeds to block704with communicating the downlink wireless network information formatted in the second protocol layer from the host unit to at least one antenna unit across at least one digital communication link. Exemplary method700proceeds to block706with converting the downlink wireless network information communication form the host unit from the second protocol layer to downlink radio frequency signals at the at least one antenna unit. Exemplary method700proceeds to block708with communicating the downlink radio frequency signals wirelessly using at least one antenna at the at least one antenna unit.

FIG. 8is a flow diagram illustrating one exemplary embodiment of a method800for efficiently transporting wireless network information through a distributed antenna system. Exemplary method800begins at block802with receiving uplink radio frequency signals wirelessly at at least one antenna unit using at least one antenna. Exemplary method800proceeds to block804with converting uplink radio frequency signals to uplink wireless network information in a second protocol layer at the at least one antenna unit. Exemplary method800proceeds to block806with communicating the uplink wireless network information formatted in the second protocol layer from the at least one antenna unit to the host unit across at least one digital communication link. Exemplary method800proceeds to block808with converting the uplink wireless network information received from the at least one antenna unit from the second protocol layer to a first protocol layer, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer. Exemplary method800proceeds to optional block810with combining uplink wireless network information received from a plurality of antenna units into aggregate uplink wireless network information. In exemplary embodiments, the uplink wireless network information is combined through summation (either digital or analog), weighted summation, averaging, multiplexing, etc.

FIG. 9is a representation of an exemplary Layer 1 (L1)/Layer 2 (L2) protocol stack900for a radio access network (RAN) implementing LTE. The protocol stack900includes a packet data convergence protocol (PDCR) layer902, a radio link control (RLC) layer904, a medium access control (MAC) layer906, and a physical (PHY) layer908. In exemplary embodiments, each of the packet data convergence protocol (PDCP) layer902, the radio link control (RLC) layer904, and the medium access control (MAC) layer906are replaced with another type of Layer 2 (L2). In exemplary embodiments, the physical (PHY) layer908is replaced with another type of Layer 1 (L1). In exemplary embodiments, at the top of the protocol stack900into the packet data convergence protocol layer902comes IP packets from the radio access network (RAN) of the LTE system. In exemplary embodiments, the IP data then flows down through the radio link control layer904to the medium access control layer906. In exemplary embodiments, going down through the various layers expands the data rate. In exemplary embodiments, there is only a slight expansion down until the medium access control layer904. Once the IP data gets to the physical layer, a much larger expansion of the data rate occurs when going to the LTE physical layer908.

In exemplary embodiments, the interface between the medium access control layer904and the LTE physical layer908is a clean interface where processing in layers above are performed by one processing device while processing lasers below are performed by another processing device. In exemplary embodiments, a processor (such as an ARM processor) performs the medium access control (MAC) layer906processing and the radio link control (RLC) layer904processing. In exemplary embodiments, a digital signal processor (DSP) performs the physical (PHY) layer908processing. In other embodiments, a System on a Chip (SoC) performs processing for the medium access control (MAC) layer906, the radio link control (RLC) layer904, and the physical (PHY) layer908. In other exemplary embodiments, a field programmable gate array (FPGA) performs all or part of the processing for the medium access control (MAC) layer906, radio link control (RLC) layer904, and/or the physical (PHY) layer908. In exemplary embodiments, the medium access control (MAC) protocol data units (PDUs) at the medium access control (MAC) layer906are transported through the distributed antenna system (such as a distributed antenna system100) instead of I/Q baseband samples (at the LTE physical layer908) because the medium access control (MAC) protocol data units (PDUs) can be more efficiently transported than the I/Q baseband samples.

FIGS. 10A-10Bare block diagrams showing interaction in an exemplary system1000of various levels of a protocol stack, such as protocol stack900. Each ofFIGS. 10A-10Billustrates a different embodiment of a system1000, labeled1000A-1000B respectively.

FIG. 10Ais a block diagram of interaction in an exemplary system1000A of various levels of a protocol stack, such as protocol stack900. The exemplary system1000A includes a radio access network interface1010A (such as a baseband unit (BBU) implemented as an eNodeB with an IP Ethernet connection to a core network or other type of baseband unit (BBU)), a host unit1030, an antenna unit1050connected to the host unit1030across a communication link1040, and a subscriber unit1070. In exemplary embodiments, the radio access network interface1010A includes a core network Layer 2 (L2)1012, a core network physical (PHY) layer1014, a radio access technology (RAT) packet data convergence protocol (PDCP) layer1016, a radio access technology (RAT) radio link control (RLC) layer1018, a radio access technology (RAT) medium access control (MAC) layer1020, and a radio access technology (RAT) physical (PHY) layer1022. In exemplary embodiments, the core network Layer 2 (L2)1012is an LTE core network Layer 2. In exemplary embodiments, the core network physical (PHY) layer1014is replaced with another type of core network Layer 1 (L1). In exemplary embodiments, the core network physical (PHY) layer1014is an LTE core network physical layer. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1016, the radio access technology (RAT) radio link control (RLC) layer1018, and the radio access technology (RAT) medium access control (MAC) layer1020are replaced with another type of radio access technology (RAT) Layer 2 (L2). In exemplary embodiments, the radio access technology (RAT) packet data convergence protocol (PDCP) layer1016is an LTE packet data convergence protocol (PDCP) layer. In exemplary embodiments, the radio access technology (RAT) radio link control (RLC) layer1018is an LTE RLC layer. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1022is replaced with another type of radio access technology (RAT) Layer 1 (L1).

In exemplary embodiments, the host unit1030includes a transport medium access control (MAC) layer1032, a radio access technology (RAT) physical (PHY) layer1034, and a transport physical (PHY) layer1036. In exemplary embodiments the transport medium access control (MAC) layer1032is replaced with another type of transport Layer 2 (L2). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1034is replaced with another type of radio access technology (RAT) Layer 1 (L1). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1034is an LTE physical (PHY) layer. In exemplary embodiments, the transport physical (PHY) layer1036is replaced with another type of transport Layer 1 (L1). In exemplary embodiments, the antenna unit1050includes a transport medium access control (MAC) layer1052, a radio access technology (RAT) physical (PHY) layer1054, and a transport physical (PHY) layer1056. In exemplary embodiments, the transport medium access control (MAC) layer1052is a transport Layer 2 (L2). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1054is a radio access technology (RAT) Layer 1 (L1). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1054is an LTE physical (PHY) layer. In exemplary embodiments, the transport physical (PHY) layer1056is a transport Layer 1 (L1). In exemplary embodiments, the subscriber unit1070includes a radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, a radio access technology (RAT) radio link control (RLC) layer1074, a radio access technology (RAT) medium access control (MAC) layer1076, and a radio access technology (RAT) physical (PHY) layer1078. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, the radio access technology (RAT) radio link control (RLC) layer1074, and the radio access technology (RAT) medium access control (MAC) layer1076is replaced with another type of radio access technology (RAT) Layer 2. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, the radio access technology (RAT) radio link control (RLC) layer1074, and the radio access technology (RAT) medium access control (MAC) layer1076are LTE Layer 2 protocol layers. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1078is replaced with another type of radio access technology (RAT) Layer 1. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1078is an LTE Layer 1 protocol layer.

In exemplary embodiments, the RAT physical (PHY) layer1034of the host unit1030is communicatively coupled to the RAT physical (PHY) layer1022of the radio access network interface1010A. In exemplary embodiments, the transport physical (PHY) layer1056of the antenna unit1050is communicatively coupled to the transport physical (PHY) layer1036of the host unit1030by the communication link1040. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1054of the antenna unit1050is coupled to an antenna1060. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1078of the subscriber unit is communicatively coupled to an antenna1080. In exemplary embodiments, the RAT physical (PHY) layer1054communicates with the RAT physical (PHY) layer1078across a wireless link between antenna1060and antenna1080.

In exemplary embodiments, the core network physical (PHY) layer1014receives core network physical (PHY) layer protocol data units (PDUs) (such as a serial data stream) from a component in a core network (such as core network622described above with reference toFIG. 6) and converts the core network physical layer PDUs into core network Layer 2 (L2) protocol data units (PDUs). In exemplary embodiments, the core network Layer 2 (L2)1012converts the core network L2 PDUs into Layer 3 (L3) protocol data units (PDUs) that are passed to the radio access technology (RAT) packet data convergence protocol (PDCP) layer1016. In exemplary embodiments, the L3 PDUs are Internet Protocol (IP) PDUs. In exemplary embodiments, the RAT PDCP layer1016converts the L3 PDUs to radio access technology (RAT) L2 PDUs that are further processed by the RAT radio link control (RLC) layer1018and the RAT medium access control (MAC) layer1020. The RAT physical (PHY) layer1022converts the RAT L2 PDUs (such as RAT MAC PDUs) into radio access technology (RAT) physical layer data and communicates the RAT physical layer data (which is LTE physical layer data in some embodiments, such as I/Q data) to the RAT physical (PHY) layer1034of the host unit1030.

In exemplary embodiments, the host unit1030receives radio access technology (RAT) physical layer data (such as LTE physical layer data) at the RAT physical (PHY) layer1034from the RAT physical (PHY) layer1022of the radio access network interface1010A. In exemplary embodiments, the RAT physical layer data is analog RF or CPRI baseband data. In exemplary embodiments, this RAT physical layer data is the data that will be transmitted over the air interface between antennas1060and antennas1080. In exemplary embodiments, the host unit1030receives the physical layer data from the RAT physical (PHY) layer1034through either a digital interface or an analog RF interface. In exemplary embodiments, the RAT physical (PHY) layer1034of the host unit1030undoes the RAT physical layer processing performed by the radio access network interface1010A and extracts just the radio access technology (RAT) medium access control (MAC) protocol data units (PDUs) in the RAT MAC layer and passes the RAT MAC PDUs (such as LTE MAC PDUs) to the RAT medium access control (MAC) layer1032. In exemplary embodiments, the RAT MAC PDUs are translated into transport medium access control (MAC) layer protocol data units (PDUs) by the transport medium access control (MAC) layer1032, such as DAS MAC PDUs. These transport MAC PDUs are sent over the communication link1040by the transport physical (PHY) layer1036(such as an Ethernet PHY or other DAS physical (PHY) processor) as synchronous serial data streams. In exemplary embodiments, packet data may be used for transport across the communication link1040. In exemplary embodiments, synchronization bits, timing bits, etc. are inserted by the transport physical (PHY) layer1036creating additional overhead. In exemplary embodiments, the communication link1040is a Category building cable (or some other lower bandwidth cable).

In exemplary embodiments, the serial stream of data is received at the transport physical (PHY) layer1056from the communication link1040. In exemplary embodiments, the transport physical (PHY) layer1056is an Ethernet PHY or some other DAS physical (PHY) layer. In exemplary embodiments, the transport physical (PHY) layer of the antenna unit1050extracts the transport medium access control (MAC) PDUs in the transport medium access control (MAC) layer1052, such as DAS transport MAC PDUs. The transport medium access control (MAC) layer1052synchronizes to the stream of received transport MAC PDUs and reframes the transport MAC PDUs into the radio access technology (RAT) medium access control (MAC) protocol data units (PDUs) in the radio access technology (RAT) medium access control (MAC) layer. These RAT MAC PDUs are run through the RAT physical (PHY) layer1054resulting in a signal that is formatted in the same way as the radio access technology (RAT) physical layer data (such as LTE physical layer data) output from the RAT physical (PHY) layer1022of the radio access network interface1010A. In exemplary embodiments, the RAT physical layer data is output via the RAT physical (PHY) layer1054and the antenna1060across the wireless link to the antenna1080of the physical (PHY) layer1078of the subscriber unit1070. By transporting across the communication link1040using the transport MAC PDUs through the transport physical (PHY), the data rate of the signals over the communication link1040is reduced.

In the uplink the antenna unit1050receives signals at the RAT physical (PHY) layer1054via the antenna1060from the subscriber unit1070, just as the radio access network interface1010A could. The RAT physical (PHY) layer1054of the antenna unit1050processes these uplink signals into uplink RAT MAC PDUs in the RAT MAC layer. The RAT MAC PDUs are translated into the transport MAC PDUs by the transport MAC layer1052. The transport MAC PDUs are converted by the transport physical (PHY) layer1056and sent over the communication link1040to the transport physical (PHY) layer1036of the host unit1030. In the host unit1030, the detected transport data streams are gathered from the antenna units104by the transport physical (PHY) layer1036(instead of I/Q RAT samples) and are converted to uplink transport MAC PDUs by the transport physical (PHY) layer1036. The uplink transport MAC PDUs are translated into uplink RAT MAC PDUs by the transport MAC layer1032.

In exemplary embodiments, the uplink data from the antenna units1050is combined in the host unit1030. In exemplary embodiments, the uplink transport MAC PDUs received from antenna units1050are intelligently combined using majority logic, soft weighted combining, averaging or other combining methods by the transport MAC layer1032. The combined MAC PDU is then translated into uplink RAT MAC PDUs by the transport MAC layer1032. In exemplary embodiments, the uplink combining is performed in the transport physical layer1036. In exemplary embodiments, the uplink combining is performed on the RAT MAC PDUs in the transport MAC layer1032. The uplink RAT MAC PDUs are communicated as RAT physical layer data by the RAT PHY layer1034to the RAT physical (PHY) layer1022of the radio access network interface1010A by the RAT physical (PHY) layer1034of the antenna unit1050. In exemplary embodiments, the RAT PHY layer1022of the radio access network interface1010A converts the RAT physical layer data into uplink RAT MAC PDUs that are passed to the RAT MAC layer1020and up through RAT RLC layer1018and RAT PDCP layer1016and converted into L3 PDUs that are communicated to the core network Layer 2 (L2)1012down the core network stack and converted into core network physical data and communicated by the core network physical layer1014to the upstream core network component.

FIG. 10Bis a block diagram of interaction in an exemplary system1000B of various levels of a protocol stack, such as protocol stack900. The exemplary system1000B includes a radio access network interface1010B (such as a baseband unit (BBU) implemented as an eNodeB with an IP Ethernet connection to a core network or other type of baseband unit (BBU)), an antenna unit1050connected to the radio access network interface1010B across a communication link1040, and a subscriber unit1070. In exemplary embodiments, the radio access network interface1010B includes a core network Layer 2 (L2)1012, a core network physical (PHY) layer1014, a radio access technology (RAT) packet data convergence protocol (PDCP) layer1016, a radio access technology (RAT) radio link control (RLC) layer1018, a radio access technology (RAT) medium access control (MAC) layer1020, a transport medium access control (MAC) layer1102, and a transport physical (PHY) layer1104. In exemplary embodiments, the core network Layer 2 (L2)1012is an LTE core network Layer 2 (L2). In exemplary embodiments, the core network physical (PHY) layer1014is replaced with another type of core network Layer 1 (L1). In exemplary embodiments, the core network physical layer1012is an LTE core network physical layer. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1016, the radio access technology (RAT) radio link control (RLC) layer1018, and the radio access technology (RAT) medium access control (MAC) layer1020is replaced with another type of radio access technology (RAT) Layer 2 (L2). In exemplary embodiments, the radio access technology (RAT) packet data convergence protocol (PDCP) layer1016is an LTE packet data convergence protocol (PDCP) layer. In exemplary embodiments, the radio access technology (RAT) radio link control (RLC) layer1018is an LTE radio link control (RLC) layer. In exemplary embodiments, the radio access technology (RAT) medium access control (MAC) layer1020is an LTE medium access control (MAC) layer. In exemplary embodiments, the transport medium access control (MAC)1102is replaced with another type of transport Layer 2 (L2). In exemplary embodiments, the transport physical (PHY) layer1104is replaced with another type of transport Layer 1 (L1).

In exemplary embodiments, the antenna unit1050includes a transport medium access control (MAC) layer1052, a radio access technology (RAT) physical (PHY) layer1054, and a transport physical (PHY) layer1056. In exemplary embodiments, the transport medium access control (MAC) layer1052is replaced with another type of transport Layer 2 (L2). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1054is replaced with another type of radio access technology (RAT) Layer 1 (L1). In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1054is an LTE physical (PHY) layer. In exemplary embodiments, the transport physical (PHY) layer1056is replaced with another type of transport Layer 1 (L1). In exemplary embodiments, the subscriber unit1070includes a radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, a radio access technology (RAT) radio link control (RLC) layer1074, a radio access technology (RAT) medium access control (MAC) layer1076, and a radio access technology (RAT) physical (PHY) layer1078. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, the radio access technology (RAT) radio link control (RLC) layer1074, and the radio access technology (RAT) medium access control (MAC) layer1076is replaced with another type of radio access technology (RAT) Layer 2. In exemplary embodiments, each of the radio access technology (RAT) packet data convergence protocol (PDCP) layer1072, the radio access technology (RAT) radio link control (RLC) layer1074, and the radio access technology (RAT) medium access control (MAC) layer1076are LTE Layer 2 protocol layers. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1078is replaced with another type of radio access technology (RAT) Layer 1. In exemplary embodiments, the radio access technology (RAT) physical (PHY) layer1078is an LTE Layer 1 protocol layer.

Distributed antenna system1000B includes similar components to distributed antenna system1000A and operates according to similar principles and methods as distributed antenna system1000A described above. The difference between distributed antenna system1000B and distributed antenna system1000A is that distributed antenna system1000B does not include the host unit1030and the radio access network interface1010B includes transport medium access control (MAC) layer1102in addition to RAT medium access control (MAC) layer1020and transport physical (PHY) layer1104instead of RAT physical (PHY) layer1022. The transport medium access control (MAC) layer1102and transport physical (PHY) layer1104enables the radio access network interface1010B to communicate directly with antenna unit1050using the transport MAC PDUs.

In exemplary embodiments in the downlink, the core network Layer (L2)1012, the core network physical layer1014, the RAT PDCP layer1016, the RAT RLC layer1018, and the RAT medium access control (MAC) layer1020function as described above with reference to the radio access network interface1010A ofFIG. 10A. The difference in the radio access network interface1010B being that the transport medium access control (MAC) layer1102converts from radio access technology (RAT) medium access control (MAC) PDUs to transport medium access control (MAC) PDUs. In exemplary embodiments, the transport physical (PHY) layer1104is implemented using Ethernet PHY devices through which the transport medium access control (MAC) PDUs are communicated across the communication link1040. These transport MAC PDUs are sent over the communication link1040by the transport physical (PHY) layer1104(such as an Ethernet PHY or other DAS physical (PHY) layer) as synchronous serial data streams. In exemplary embodiments, packet data may be used for transport across the communication link1040. In exemplary embodiments, synchronization bits, timing bits, etc. are inserted by the transport physical (PHY) layer1036creating additional overhead. In exemplary embodiments, the communication link1040is a Category building cable (or some other lower bandwidth cable).

In exemplary embodiments, the serial stream of data is received at the transport physical (PHY) layer1058from the communication link1040. In exemplary embodiments, the transport physical (PHY) layer1058is implemented using Ethernet PHY devices or some other DAS physical (PHY) layer. In exemplary embodiments, the transport physical (PHY) layer of the antenna unit1050extracts the transport medium access control (MAC) PDUs in the transport medium access control (MAC) layer1054, such as DAS transport MAC PDUs. The transport medium access control (MAC) layer1054synchronizes to the stream of received transport MAC PDUs and reframes the transport MAC PDUs into the radio access technology (RAT) medium access control (MAC) protocol data units (PDUs) in the radio access technology (RAT) medium access control (MAC) layer. These RAT MAC PDUs are run through the RAT physical (PHY) layer1056resulting in a signal that is formatted in the same way as the radio access technology (RAT) physical layer data (such as LTE physical layer data) output from the RAT physical (PHY) layer1022of the radio access network interface1010A. In exemplary embodiments, the RAT physical layer data is output via the RAT physical (PHY) layer1056and the antenna1060across the wireless link to the antenna1080of the physical (PHY) layer1078of the subscriber unit1070. By transporting across the communication link1040using the transport MAC PDUs through the transport physical (PHY) layer, the data rate of the signals transported over the communication link1040is reduced.

In the uplink the antenna unit1050receives signals at the RAT physical (PHY) layer1056via the antenna1060from the subscriber unit1070, just as the radio access network interface1010A could. The RAT physical (PHY) layer1056of the antenna unit1050processes these uplink signals into uplink RAT MAC PDUs in the RAT MAC layer. The RAT MAC PDUs are translated into the transport MAC PDUs by the transport MAC layer1054. The transport MAC PDUs are converted by the transport physical (PHY) layer1058and sent over the communication link1040to the transport physical (PHY)1104of the radio access network interface1010B. In the radio access network interface1010B, the detected transport data streams are gathered from the antenna units1050by the transport physical (PHY)1104(instead of I/Q RAT samples) and are converted to uplink transport MAC PDUs by the transport physical (PHY) layer1104. The uplink transport MAC PDUs are translated into uplink RAT MAC PDUs by the transport MAC layer1102and communicated to the RAT medium access control (MAC)1020of the radio access network interface1010B. In the radio access network interface1010B, the information is communicated up the RAT/transport side of the protocol stack in the radio access network interface1010B and down the core network side of the protocol stack1010B as described above with reference to radio access network interface1010A.

In exemplary embodiments, the uplink data from the antenna units1050is combined in the radio access network interface1010B. In exemplary embodiments the uplink transport MAC PDUs received from antenna units1050are intelligently combined using majority logic, soft weighted combining, averaging or other combining methods by the transport MAC layer1102. The combined MAC PDU is then translated into uplink RAT MAC PDUs by the transport MAC layer1102. In exemplary embodiments the uplink combining is performed in the transport physical layer1104. In exemplary embodiments the uplink combining is performed on the RAT MAC PDUs in the transport MAC layer1102.

In exemplary embodiments, any of the processors described above may include or function with software programs, firmware or other computer readable instructions for carrying out various methods, process tasks, calculations, and control functions, used in the digital processing functionality described herein. These instructions are typically stored on any appropriate computer readable medium used for storage of computer readable instructions or data structures. The computer readable medium can be implemented as any available media that can be accessed by a general purpose processor (GPP) or special purpose computer or processor (such as a field-programmable gate array (FPGA), application-specific integrated circuit (ASIC) or other integrated circuit), or any programmable logic device. Suitable processor-readable media may include storage or memory media such as magnetic or optical media. For example, storage or memory media may include conventional hard disks, Compact Disk-Read Only Memory (CD-ROM), volatile or non-volatile media such as Random Access Memory (RAM) (including, but not limited to, Synchronous Dynamic Random Access Memory (SDRAM), Double Data Rate (DDR) RAM, RAMBUS Dynamic RAM (RDRAM), Static RAM (SRAM), etc.), Read Only Memory (ROM), Electrically Erasable Programmable ROM (EEPROM), and flash memory, etc. Suitable processor-readable media may also include transmission media such as electrical, electromagnetic, or digital signals, conveyed via a communication medium such as a network and/or a wireless link.

Example Embodiments

Example 1 includes a distributed antenna system comprising: a host unit configured to receive downlink wireless network information from a radio access network interface; at least one antenna unit communicatively coupled to the host unit by at least one digital communication link; wherein the host unit is configured to convert the downlink wireless network information received from the radio access network interface from a first protocol layer to a second protocol layer, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer; wherein the host unit is configured to communicate the downlink wireless network information to the at least one antenna unit across the at least one digital communication link; wherein the at least one antenna unit is configured to convert the downlink wireless network information communicated from the host unit from the second protocol layer to downlink radio frequency signals; and wherein the at least one antenna unit is configured to communicate the downlink radio frequency signals wirelessly using at least one antenna.

Example 2 includes the distributed antenna system of Example 1, wherein the at least one antenna unit is configured to convert the downlink wireless network information communicated from the host unit from the second protocol layer to downlink radio frequency signals by being configured to: convert the downlink wireless network information communicated from the host unit from the second protocol layer to the first protocol layer; convert the downlink wireless network information from digital signals to analog signals; and frequency convert the downlink wireless network information from baseband signals to downlink radio frequency signals.

Example 3 includes the distributed antenna system of any of Examples 1-2, wherein the host unit is further configured to convert the downlink wireless network information from a first protocol data unit type to a second protocol data unit type before the downlink wireless network information are communicated from the host unit to the at least one antenna unit across the at least one digital communication link.

Example 4 includes the distributed antenna system of Example 3, wherein the at least one antenna unit is further configured to convert the downlink wireless network information from the second protocol data unit type to the first protocol data unit type before the downlink wireless network information are converted from the second protocol layer to downlink radio frequency signals.

Example 5 includes the distributed antenna system of any of Examples 1-4, further comprising: wherein the at least one antenna unit is further configured to receive uplink radio frequency signals wirelessly using at least one antenna; wherein the at least one antenna unit is further configured to convert the uplink radio frequency signals to uplink wireless network information in the second protocol layer; wherein the at least one antenna unit is further configured to communicate the uplink wireless network information to the host unit across the at least one digital communication link; and wherein the host unit is configured to convert the uplink wireless network information received from the at least one antenna unit from the second protocol layer to the first protocol layer.

Example 6 includes the distributed antenna system of any of Examples 1-5, wherein at least a first digital communication link of the at least one digital communication link is transported across a medium that is a Category building cabling.

Example 7 includes the distributed antenna system of any of Examples 1-6, wherein the digital communication link is implemented using Ethernet physical layer devices.

Example 8 includes the distributed antenna system of any of Examples 1-7, wherein the first protocol layer is a physical layer and the second protocol layer is a medium access control layer.

Example 9 includes the distributed antenna system of any of Examples 1-8, wherein the first protocol layer is a Long Term Evolution (LTE) physical layer and the second protocol layer is a medium access control layer.

Example 10 includes a distributed antenna system comprising: a host unit configured to transmit uplink wireless network information to a radio access network interface; at least one antenna unit communicatively coupled to the host unit by at least one digital communication link; wherein the at least one antenna unit is configured to receive uplink radio frequency signals wirelessly using at least one antenna; wherein the at least one antenna unit is further configured to convert the uplink radio frequency signals to uplink wireless network information in a second protocol layer; wherein the at least one antenna unit is further configured to communicate the uplink wireless network information to the host unit across the at least one digital communication link; and wherein the host unit is configured to convert the uplink wireless network information received from the at least one antenna unit from the second protocol layer to a first protocol layer, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer.

Example 11 includes the distributed antenna system of Example 10, wherein the at least one antenna unit is configured to convert the uplink radio frequency signals to uplink wireless network information in a second protocol layer by being configured to: frequency convert the uplink wireless network information from uplink radio frequency signals to baseband signals; convert the uplink wireless network information from analog signals to digital signals; convert the uplink wireless network information from the first protocol layer to the second protocol layer.

Example 12 includes the distributed antenna system of any of Examples 10-11, wherein at least a first digital communication link of the at least one digital communication link is transported across a medium that is a Category building cabling.

Example 13 includes the distributed antenna system of any of Examples 10-12, wherein the first digital communication link is implemented using Ethernet physical layer devices.

Example 14 includes the distributed antenna system of any of Examples 10-13, wherein the host unit is further configured to combine multiple uplink wireless network information received from a plurality of antenna units together.

Example 15 includes the distributed antenna system of Example 14, wherein the host unit is further configured to combine multiple uplink wireless network information received from the plurality of antenna units together using at least one of majority logic and weighted combining.

Example 16 includes the distributed antenna system of any of Examples 14-15, wherein the host unit is further configured to combine multiple uplink wireless network information received from the plurality of antenna units together based on quality metrics received from the plurality of antenna units.

Example 17 includes the distributed antenna system of any of Examples 10-16, wherein the first protocol layer is a physical layer and the second protocol layer is a medium access control layer.

Example 18 includes the distributed antenna system of any of Examples 10-17, wherein the first protocol layer is a Long Term Evolution (LTE) physical layer and the second protocol layer is a medium access control layer.

Example 19 includes a method for efficiently transporting wireless network information through a distributed antenna system, comprising: converting downlink wireless network information received from a radio access network interface from a first protocol layer to a second protocol layer at a host unit in a distributed antenna system, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer; communicating the downlink wireless network information from the host unit to at least one antenna unit across at least one digital communication link; converting the downlink wireless network information communicated from the host unit from the second protocol layer to downlink radio frequency signals at the at least one antenna unit; communicating the downlink radio frequency signals wirelessly using at least one antenna at the at least one antenna unit.

Example 20 includes the method of Example 19, wherein converting the downlink wireless network information communicated from the host unit from the second protocol layer to the downlink radio frequency signals at the at least one antenna unit includes: converting the downlink wireless network information communicated from the host unit from the second protocol layer to the first protocol layer; converting the downlink wireless network information from digital signals to analog signals; and frequency converting the downlink wireless network information from baseband signals to downlink radio frequency signals.

Example 21 includes the method of any of Examples 19-20, further comprising converting the downlink wireless network information from a first protocol data unit type to a second protocol data unit type at the host unit before the downlink wireless network information are communicated from the host unit to the at least one antenna unit across the at least one digital communication link.

Example 22 includes the method of Example 21, further comprising converting the downlink wireless network information from the second protocol data unit type to the first protocol data unit type at the at least one remote antenna unit before the downlink wireless network information are converted from the second protocol layer to downlink radio frequency signals.

Example 23 includes the method of any of Examples 19-22, further comprising: receiving uplink radio frequency signals wirelessly at the at least one antenna unit using the at least one antenna; converting uplink radio frequency signals to uplink wireless network information in the second protocol layer at the at least one antenna unit; communicating the uplink wireless network information from the at least one antenna unit to the host unit across the at least one digital communication link; and converting the uplink wireless network information received from the at least one antenna unit from the second protocol layer to the first protocol layer.

Example 24 includes the method of any of Examples 19-23, wherein the first protocol layer is a physical layer and the second protocol layer is a medium access control layer.

Example 25 includes the method of any of Examples 19-24, wherein the first protocol layer is a Long Term Evolution (LTE) physical layer and the second protocol layer is a medium access control layer.

Example 26 includes a method for efficiently transporting wireless network information through a distributed antenna system, comprising: receiving uplink radio frequency signals wirelessly at at least one antenna unit using at least one antenna; converting uplink radio frequency signals to uplink wireless network information in a second protocol layer at the at least one antenna unit; communicating the uplink wireless network information from the at least one antenna unit to the host unit across at least one digital communication link; and converting the uplink wireless network information received from the at least one antenna unit from the second protocol layer to a first protocol layer, wherein the second protocol layer uses relevant bits more efficiently than the first protocol layer.

Example 27 includes the method of Example 26, wherein converting uplink radio frequency signals to uplink wireless network information in the second protocol layer at the at least one antenna unit includes: frequency converting the uplink wireless network information from uplink radio frequency signals to baseband signals; converting the uplink wireless network information from analog signals to digital signals; converting the uplink wireless network information from the first protocol layer to the second protocol layer.

Example 28 includes the method of any of Examples 26-27, wherein the first protocol layer is a physical layer and the second protocol layer is a medium access control layer.

Example 29 includes the method of any of Examples 26-28, wherein the first protocol layer is a Long Term Evolution (LTE) physical layer and the second protocol layer is a medium access control layer.

Example 30 includes a distributed antenna system comprising: a host unit configured to receive downlink LTE physical layer data from an eNodeB; at least one antenna unit communicatively coupled to the host unit by at least one digital communication link; wherein the host unit is configured to convert the downlink LTE physical layer data in the LTE physical layer to downlink LTE medium access control layer protocol data units in the LTE medium access control layer, wherein the LTE medium access control layer uses relevant bits more efficiently than the LTE physical layer; wherein the host unit is configured to convert the downlink LTE medium access control layer protocol data units in the LTE medium access control layer into downlink distributed antenna system transport medium access control layer protocol data units in a downlink distributed antenna system transport medium access control layer for transport through the distributed antenna system; wherein the host unit is configured to convert the downlink distributed antenna system transport medium access control layer protocol data units in the downlink distributed antenna system transport medium access control layer into a downlink Ethernet physical layer data stream in the Ethernet physical layer; wherein the host unit is configured to communicate the downlink Ethernet physical layer data stream across the digital communication link to the at least one antenna unit; wherein the at least one antenna unit is configured to receive the downlink Ethernet physical layer data stream from the host unit across the digital communication link; wherein the at least one antenna unit is configured to convert the downlink Ethernet physical layer data stream in the Ethernet physical layer to the downlink distributed antenna system transport medium access control layer protocol data units in the downlink distributed antenna system transport medium access control layer; wherein the at least one antenna unit is configured to convert the downlink distributed antenna system transport medium access control layer protocol data units in the downlink distributed antenna system transport medium access control layer into the downlink LTE medium access control layer protocol data units in the LTE medium access control layer; wherein the at least one antenna unit is configured to generate a downlink LTE radio frequency signal from the downlink LTE medium access control layer protocol data units in the LTE medium access control layer; and wherein the at least one antenna unit is configured to communicate the downlink LTE radio frequency signal using at least one antenna.

Example 31 includes a distributed antenna system comprising: a host unit; at least one antenna unit communicatively coupled to the host unit by at least one digital communication link and configured to receive an uplink LTE radio frequency signal using at least one antenna; wherein the at least one antenna unit is configured to generate uplink LTE medium access control layer protocol data units in the LTE medium access control layer from the uplink LTE radio frequency signal; wherein the at least one antenna unit is configured to convert the uplink LTE medium access control layer protocol data units in the LTE medium access control layer into uplink distributed antenna system transport medium access control layer protocol data units in an uplink distributed antenna system transport medium access control layer; wherein the at least one antenna unit is configured to convert the uplink distributed antenna system transport medium access control layer protocol data units in the uplink distributed antenna system transport medium access control layer into an uplink Ethernet physical layer data stream in an Ethernet physical layer; wherein the at least one antenna unit is configured to communicate the uplink Ethernet physical layer data stream to the host unit across the digital communication link; wherein the host unit is configured to receive the uplink Ethernet physical layer data stream across the digital communication link from the at least one antenna unit; wherein the host unit is configured to convert the uplink Ethernet physical layer data stream in the Ethernet physical layer into uplink distributed antenna system transport medium access control layer protocol data units in the uplink distributed antenna system transport medium access control layer; wherein the host unit is configured to convert the uplink distributed antenna system transport medium access control layer protocol data units in the uplink distributed antenna system transport medium access control layer into uplink LTE medium access control layer protocol data units in the LTE medium access control layer; and wherein the host unit is configured to convert the uplink LTE medium access control layer protocol data units in the LTE medium access control layer into uplink LTE physical layer data in the LTE physical layer, wherein the LTE medium access control layer uses relevant bits more efficiently than the LTE physical layer.