Patent Description:
Next generation wireless communication systems are expected to be a unified network/system that is targeted to meet vastly different and sometimes conflicting performance dimensions and services. New Radio Access Technology (RAT) is expected to support a broad range of use cases including Enhanced Mobile Broadband (eMBB), Massive Machine Type Communication (mMTC), Mission Critical Machine Type Communication (uMTC), and similar service types operating in frequency ranges up to <NUM>.

3GPP document R1-<NUM> discloses that the presence/patterns of PT-RS are configured by a combination of RRC signaling and association with parameter(s) used for other purposes (e.g., MCS) which are (dynamically) indicated by DCI.

It will nevertheless be understood that no limitation of the scope of the technology is thereby intended.

Before the present technology is disclosed and described, it is to be understood that this technology is not limited to the particular structures, process actions, or materials disclosed herein, but is extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular examples only and is not intended to be limiting. The same reference numerals in different drawings represent the same element. Numbers provided in flow charts and processes are provided for clarity in illustrating actions and operations and do not necessarily indicate a particular order or sequence. The scope of protection of the invention is defined by the appended claims.

Mobile communication has evolved significantly from early voice systems to today's highly sophisticated integrated communication platform. Mechanisms are disclosed for configuration of downlink (DL) control channel monitoring occasions. Additionally, different options for defining UE behavior and handling of multiple DL control channel monitoring configurations from a single UE perspective are disclosed. The next generation wireless communication system, <NUM>, or new radio (NR) will provide access to information and sharing of data anywhere, at any time by various users and applications. NR is expected to be a unified network/system that is targeted to meet vastly different and sometime conflicting performance dimensions and services.

For a system operating in a high frequency band, e.g. ><NUM>, to compensate the phase offset resulting from phase noise and frequency offset, a Phase Tracking Reference Signal (PT-RS) can be used for the symbols that are not using a Demodulation Reference Signal (DM-RS).

<FIG> illustrates an example for phase tracking reference signal (PT-RS) mapping. Dynamic presence and time/frequency densities of the PT-RS transmission can be determined by a Modulation and Coding Scheme (MCS), a Subcarrier Spacing (SCS) and an allocated bandwidth (BW) for a physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) allocation in a bandwidth part (BWP). However for different bandwidth parts (BWPs), the SCS may be different. If a UE is allocated with multiple bandwidth parts, determining the dynamic presence and time/frequency density of PT-RS is considered. In one embodiment, a PT-RS can be included in one or more reference elements (REs) in each symbol of a slot of the PDSCH/PUSCH that does not include a DMRS. In addition to the DMRS, there can be an offset of symbols at the beginning of an allocation that do not include the PT-RS.

Further, the symbol index of a front-loaded DM-RS for DL data transmission, can be fixed. For dynamic resource sharing of control and data, the associated downlink (DL) or uplink (UL) data can be multiplexed with a DL or an UL control channel in a frequency division multiplexing (FDM) manner. Accordingly, <FIG> and <FIG> illustrate that a data channel may be transmitted starting from the first symbol within one slot, before the DMRS transmission in a downlink slot. In the example of <FIG>, a PDCCH can be included in the first and/or first and second symbols of a downlink slot. In the example of <FIG>, a PUCCH can be included in the last two symbols of an uplink slot. Accordingly, solutions for PT-RS dynamic presence and time/frequency densities design for multiple bandwidth part allocation are disclosed. Additionally, solutions for PT-RS resource mapping when a physical downlink shared channel (PDSCH) shares the resource with a physical downlink control channel (PDCCH), and when a physical uplink shared channel (PUSCH) shares the resource with physical uplink control channel (PUCCH), are also disclosed.

If a UE is scheduled with multiple bandwidth parts (BWPs), it is possible that different subcarrier spacing (SCS) may be used in different bandwidth parts. The SCS, the MCS and the allocated BW could have some impact on the dynamic presence and time/frequency densities of PT-RS. Hence, when a UE is allocated with multiple bandwidth parts, determining the dynamic presence and density of PT-RS can be considered.

<FIG> illustrates an example for a user equipment (UE) with multiple bandwidth parts (BWPs) with different subcarrier spacing (SCS). In an embodiment, a dynamic presence, a time density and a frequency density of PT-RS in each bandwidth part can be independently determined by the allocated bandwidth (BW) and SCS in the bandwidth part, as well as the MCS used in the bandwidth part, if a UE is scheduled with multiple bandwidth parts.

In one example, if the UE is allocated two bandwidth parts, SCS k1 is used for bandwidth part <NUM>, and SCS k2 is used for bandwidth part <NUM>, where the range of k1 and k2 can be included but not limited to the range of <NUM> kilohertz (kHz), <NUM>, <NUM>, or <NUM>. Additionally, the PT-RS pattern can be independently determined by each bandwidth when k1≠k2. On the other hand, if k1=k2, the PT-RS pattern can be jointly determined by the allocated bandwidth in both bandwidth parts or determined by the allocated bandwidth in each bandwidth part independently.

Further, in another embodiment, if a UE is allocated, based an integer N, the UE can be configured with N><NUM> bandwidth parts. In some instances, some BWPs can utilize different SCS. In one option, dynamic presence and density of a PT-RS for each bandwidth part can be determined by an SCS, an MCS and an allocated BW for each bandwidth part independently. In another option, it can be determined jointly for some variations of BW with the same SCS. <FIG> illustrates one example for the PT-RS transmission for multiple bandwidth parts.

The data channel may be multiplexed with a PDCCH or a PUCCH, a Channel State Information Reference Signal (CSI-RS), and a Sounding Reference Signal (SRS) or a Synchronization Signal (SS) block. Accordingly, some subcarriers in one symbol may be used by other signals. The use of other subcarriers can be taken into account in order to determine the dynamic presence and time/frequency densities for PT-RS.

In an embodiment, the PT-RS can be transmitted starting from the first data symbol regardless of whether or not the PDCCH is transmitted. In another option, PT-RS can be transmitted at the first symbol(s) where there is not a PDCCH. Further the PT-RS may not be transmitted at the symbol where there is a PUCCH or a CSI-RS or an SS block. In these instances, the PT-RS may be punctured to include the PDCCH, PUCCH, CSI-RS, or SS block.

In an alternative, PT-RS can be transmitted at the symbol where there is a PDCCH, a PUCCH, a CSI-RS or an SS block. The frequency domain density for each symbol may be determined independently, given the scheduled BW is NRS, and the other signal transmitted in the same symbol uses K<NUM> subcarriers. The bandwidth that is used to determine the dynamic presence and the frequency density for this symbol is calculated by <MAT>, where <MAT> refers to the number of subcarriers per Resource Block (RB) and K<NUM> is the number of subcarriers for other signals in the same symbol. Further, a threshold, X, can be determined or defined, where a relative amount of remaining bandwidth is less than X, then the PT-RS is not transmitted. X can be a number between <NUM> and <NUM>.

<FIG> illustrates an example for the PT-RS transmission when multiplexing with other signals with the same SCS. In one embodiment, for dynamic sharing of a DL or an UL control and data in the same symbols within one slot, the starting position of a DL data transmission can be dynamically indicated and explicitly indicated in a UE specific downlink control information (DCI) or a group common PDCCH or group common DCI.

In one embodiment, for a case where the DCI signals a DL data starting symbol equal to or less than a control resource set (CORESET) duration in the time domain, the DL data channel can either be rate matched around the control resource set for DL control channel or around the resources actually used for transmission of the DL control channel.

In this case, the starting position of a PT-RS may be aligned with the transmission of a DL data channel. Within the frequency resource, where the DL data channel is rate matched around the control resource set or the resources actually used for the transmission of the DL control channel, the starting position of the PT-RS can be aligned with that of the DL data transmission.

<FIG> illustrates an example of PT-RS pattern for dynamic resource sharing of DL control and data channel. In one example, a PT-RS starting position is aligned with a DL data transmission. In particular, a PT-RS can start from the first symbol in the frequency resource where the DL data channel does not overlap with the DL control channel in the first symbol. Further, the PT-RS can start from the second symbol in the frequency resource where the DL data channel is rate matched around the PDCCH.

As an alternative, the starting position of the PT-RS is the same, relative to the starting position of the DL data channel signaled in the UE specific DCI in the case of the dynamic resource sharing of the DL control and DL data channel. In particular, it can be the same as the starting position of the DL data channel signaled in the UE specific DCI, the first symbol after the control resource set (CORESET), or the resource used for the transmission of the DCI. In the former case, the PT-RS may puncture the PDCCH in the first few symbols.

<FIG> illustrates another example of a PT-RS pattern for dynamic resource sharing of DL control and data channel. In the example displayed by <FIG>, the PT-RS starting position is the second symbol in the slot, which is the first symbol after the PDCCH.

In one embodiment, in the case when the physical uplink share channel (PUSCH) and the physical uplink control channel (PUCCH) are multiplexed in a frequency division multiplexing (FDM) manner in the last symbol(s) within a slot from the same or different UEs, as previously illustrated in <FIG>, the PT-RS end position can be aligned with the PUSCH end position.

<FIG> illustrates an example of a PT-RS end position when physical uplink shared channel (PUSCH) and physical uplink control channel (PUCCH) are multiplexed in a frequency division multiplexing manner in the last symbol(s). In one example, where the frequency resource of the PUSCH and the PUCCH overlap, the PT-RS end position is located in the second to last symbol. Further, in the frequency resource where the PUSCH and the PUCCH do not overlap, the PT-RS end position is located in the last symbol within a slot.

As an alternative, the end position of the PT-RS can be the same symbol within a slot, relative to the end position of the PUSCH in the case when the PUSCH and the PUCCH are multiplexed in an FDM manner in the last symbol(s). In particular, it can be the same symbol as the end position of the PUSCH signaled in the UE specific DCI or the first symbol before the PUCCH transmission.

<FIG> illustrates an example for the PT-RS transmission when multiplexing with other signals with different SCS. In one embodiment, the larger SCS may be used for the CSI-RS or the sounding reference signal (SRS) for beam management, where the data may also be multiplexed to the remaining subcarriers at the CSI-RS or SRS symbol. Additionally, the presence and time/frequency density for the PT-RS in that symbol can be independently determined by the SCS, the BW and the MCS in that symbol.

<FIG> illustrates an example for PT-RS transmission when frequency hopping is used. In one embodiment, when the frequency hopping is enabled for the data channel, the PT-RS can also be used within the bandwidth where the UL and the DL data are transmitted. Additionally, for the two DM-RS symbols as shown in the first part of the slot in <FIG>, the design can be applied for the case when one DM-RS symbol is configured in the first part of the slot.

Additionally, the Phase Tracking Reference Signal (PT-RS) is used to compensate for the phase noise and the frequency offset impact for the high frequency band, such as frequency bands greater than <NUM> gigahertz. The dynamic presence, the time density and the frequency density of the PT-RS can be determined by a Modulation and Coding Scheme (MCS), a subcarrier spacing (SCS) and an allocated bandwidth (BW). However, the phase noise characteristic may depend on the gNB and the UE implementation and could be different in a different gNB and a different UE. As such, defining a common MCS/SCS/BW for dynamic presence and time/frequency density mapping table can be utilized to reflect different phase noise levels in a different gNB and a different UE when determining the transmission of the PT-RS. In some embodiments, power boosting in DM-RS can be utilized to enhance the performance and provide power boosting for PT-RS.

In addition, a time domain Orthogonal Cover Code (TD-OCC) may be used in CSI-RS, DMRS and PUCCH. But due to phase noise impact, the time domain channel may be different in some symbols, enlisting the following solutions to compensate the phase noise impact for TD-OCC.

The dynamic presence and time/frequency density of PT-RS can be determined by the MCS, BW and SCS. One example is illustrated in the table in <FIG> which illustrates an exemplary table illustrating an example of a PT-RS configuration.

In an embodiment, with regard to different phase noise levels and forward compatibility support, there can be N number of tables used for the dynamic presence and the time/frequency density determination configured by higher layer signaling, where N is a positive integer. Then, the UE may report which table(s) to be recommended by the UE capability or other higher layer signaling. The table used for a UE can be configured by higher layer signaling or indicated in the Downlink Control Information (DCI) or a combination thereof.

There may be some benefits for the DM-RS with power boosting. The power of each subcarrier of data and DM-RS may be different. For PT-RS, the same method may bring in some benefits, especially when the density of PT-RS is lower than that of the DM-RS.

In an embodiment, the ratio of energy per resource element (EPRE) of the PT-RS and the EPRE of the PDSCH can be configured by higher layer signaling, the DCI or a combination thereof. Accordingly, different transmission powers can be used in subcarriers used for the PT-RS and the PDSCH. Alternatively, the same EPRE for the DM-RS can be applied for the transmission of the PT-RS. In one case, the separate signaling for the EPRE of the DM-RS and the PT-RS can be configured to not be utilized.

In another embodiment, the PT-RS EPRE and the PDSCH EPRE or the PUSCH EPRE can be considered. Accordingly, the following PT-RS EPRE ratios can be considered. In one example, the ratio of the PT-RS EPRE to the PDSCH or PUSCH EPRE is equal to <NUM> decibels (dB) for the PT-RS antenna port associated with <NUM> MIMO layer or <NUM> DM-RS antenna port and 3dB for the PT-RS associated with <NUM> MIMO layers or <NUM> DM-RS antenna ports. For example, in the case of a <NUM> MIMO layer transmission to the UE, the PT-RS may have a 3dB higher transmission power relative to the power of the PDSCH or the PUSCH. The 3dB power boosting is due to the use of a single antenna port transmission for the PT-RS compared to two DM-RS antenna port transmissions, which allows for full power allocation to the antenna port, while using power splitting between the DM-RS antenna ports.

In another example, the PT-RS power boosting can be further increased above 3dB relative to the PDSCH or the PUSCH, if FDM multiplexing or zero power (ZP) PT-RS are used for PT-RS transmission. For example, in the case of when the zero power PT-RS is used with the same density as non-zero power (NZP) PT-RS, the PT-RS power boosting can be <NUM> dB relative to the PDSCH or the PUSCH.

In another example, the PT-RS EPRE ratio for the PDSCH is not defined for Quadrature Phase Shift Keying (QPSK) modulation to facilitate flexible power boosting to PT-RS. The UE may not assume constant EPRE for PT-RS REs across all OFDM symbol in the slot.

In another example, the PT-RS EPRE ratio to the PDSCH can be predefined for a <NUM> Quadrature Amplitude Modulation (QAM), a <NUM> QAM, a <NUM> QAM, a <NUM> QAM, and a <NUM> QAM modulation, and all desired modulations for the PUSCH. The UE can assume constant EPRE for the PT-RS resource elements (REs) across all OFDM symbols in the slot.

Additionally, there can be an offset of P<NUM> for power control of the PT-RS and the PUSCH, where P<NUM> is a parameter configured by radio resource control (RRC) parameters. The simplified power control equation of PUSCH can be given by: <MAT>.

Additionally, where PL indicates the pathloss including the gNB and UE beamforming gain, alpha (α) represents a parameter configured by RRC, and Pmax is the maximum power that can be configured by higher layer or limited by its physical hardware.

Then the power control for PT-RS can be as follows: <MAT> Where A denotes the offset configured by higher layer signaling or DCI.

The TD-OCC can be used to distinguish the signal from different antenna ports (APs). It is assumed that the channel can be similar in those subcarriers. <FIG> illustrates an example for time division orthogonal cover code <NUM> (TD-OCC4). In an embodiment, with regard to the phase noise impact, the PT-RS should be transmitted associated with the signal where there is TD-OCC. The PT-RS and the signal with TD-OCC can be multiplexed in a Frequency Division Multiplexing (FDM) manner. The PT-RS can share one or some of APs as the APs of the signal with TD-OCC, which can be pre-defined or configured by higher layer signaling or DCI. In this case, same TD-OCC is applied for the transmission of signal and PT-RS.

<FIG> illustrates an example for PT-RS associated with a time division orthogonal cover code (TD-OCC) signal. In an embodiment, the dynamic presence and time/frequency density of PT-RS associated with signal with TD-OCC can be configured by higher layer signaling or DCI or determined by SCS and/or BW and/or MCS. If it is dynamically determined by SCS/BW/MCS, defining N tables in a first embodiment can be applied, where N is a positive integer.

<FIG> depicts functionality <NUM> of a next generation node B (gNB), operable to use phase tracking reference signals (PT-RS). The gNB can comprise one or more processors configured to determine a modulation and coding scheme (MCS) for the UE for a bandwidth part (BWP) with a subcarrier spacing (SCS) <NUM>. The gNB can comprise one or more processors configured to select a time density of the PT-RS based on the MCS <NUM>. The gNB can comprise one or more processors configured to select a frequency density of the PT-RS based on an allocated bandwidth in the BWP <NUM>. The gNB can comprise one or more processors configured to encode the time density and the frequency density, for the PT-RS for transmission to the UE in higher layer signaling <NUM>.

In one embodiment, the one or more processors are further configured to encode the PT-RS for transmission to the UE in the BWP, with the PT-RS starting at a first data symbol that is not used by a demodulation reference symbol (DM-RS) in a physical downlink shared channel (PDSCH) allocation.

In one embodiment, the one or more processors are further configured to encode the PT-RS for transmission to the UE at a resource element that is not used by a physical downlink control channel (PDCCH), a channel state information reference signal (CSI-RS), or a synchronization signal (SS) block.

In one embodiment, the one or more processors are further configured to determine an MCS and an SCS for the UE for each of a plurality of BWPs; select a time density of the PT-RS for each BWP in the plurality of BWPs, based on the MCS of the BWP; select a frequency density of the PT-RS for each BWP in the plurality of BWPs based on an allocated bandwidth of each respective BWP.

In one embodiment, the one or more processors are further configured to decode a time density of an uplink (UL) PT-RS, received from the UE, for a BWP, based on an MCS of the BWP; decode a frequency density of a UL PT-RS, received from the UE, for the BWP, based on the allocated bandwidth of the BWP.

In one embodiment, the one or more processors are further configured to decode a time density of an uplink (UL) PT-RS, received from the UE, for each BWP in a plurality of BWPs, based on an MCS of each respective BWP; decode a frequency density of a UL PT-RS, received from the UE, for each BWP in the plurality of BWPs based on the allocated bandwidth of each respective BWP.

In one embodiment, the one or more processors are further configured to decode the PT-RS received from the UE in the BWP, with the PT-RS starting at a first data symbol that is not used by a demodulation reference symbol (DM-RS) in a physical uplink shared channel (PUSCH) allocation.

In one embodiment, the one or more processors are further configured to determine a dynamic presence of the PT-RS based on the MCS, the allocated bandwidth in the BWP and the presence of a signal with a time domain orthogonal cover code (TD-OCC).

In one embodiment, the one or more processors are further configured to encode the PT-RS for transmission to the UE in the BWP when the TD-OCC is not transmitted.

<FIG> depicts functionality <NUM> of a user equipment (UE), operable to use phase tracking reference signals (PT-RS). The UE can comprise one or more processors configured to decode a modulation and coding scheme (MCS) received from a next generation node B (gNB) for a bandwidth part (BWP) with a subcarrier spacing (SCS) <NUM>. The UE can comprise one or more processors configured to decode, a higher layer signal that includes a time density of the PT-RS based on the MCS for the BWP <NUM>. The UE can comprise one or more processors configured to decode, the higher layer signal that includes a frequency density of the PT-RS based on an allocated bandwidth in the BWP <NUM>. The UE can comprise one or more processors configured to demodulate symbols received in a physical downlink shared channel (PDSCH) that are associated with the PT-RS, using the PT-RS <NUM>.

In one embodiment, the one or more processors are further configured to decode the PT-RS received from the gNB in the BWP, with the PT-RS starting at a first data symbol after a demodulation reference symbol (DM-RS) in a physical downlink shared channel (PDSCH) allocation.

In one embodiment, the one or more processors are further configured to decode the symbols in the PDSCH, wherein the PT-RS received from the gNB in the PDSCH is not included in a resource element that is used for a physical downlink control channel (PDCCH), a channel state information reference signal (CSI-RS), or a synchronization signal (SS) block.

In one embodiment, the one or more processors are further configured to decode an MCS and an SCS for the UE for each of a plurality of BWPs; decode a time density of the PT-RS for each BWP in the plurality of BWPs, based on the MCS of the BWP; decode a frequency density of the PT-RS for each BWP in the plurality of BWPs based on an allocated bandwidth of each respective BWP.

In one embodiment, the one or more processors are further configured to encode a time density of an uplink (UL) PT-RS, for transmission to the gNB, for a BWP, based on an MCS of the BWP; encode a frequency density of a UL PT-RS, for transmission to the gNB, for the BWP, based on the allocated bandwidth of the BWP.

In one embodiment, the one or more processors are further configured to encode a time density of an uplink (UL) PT-RS, for transmission to the gNB, for each BWP in a plurality of BWPs, based on an MCS of each respective BWP; encode a frequency density of a UL PT-RS, for transmission to the gNB, for each BWP in the plurality of BWPs based on the allocated bandwidth of each respective BWP.

In one embodiment, the one or more processors are further configured to encode the PT-RS, for transmission to the gNB, with the PT-RS starting at a first data symbol that is not used by a demodulation reference symbol (DM-RS) in a physical uplink shared channel (PUSCH).

In one embodiment, the UE includes an antenna, a touch sensitive display screen, a speaker, a microphone, a graphics processor, an application processor, an internal memory, a non-volatile memory port, or combinations thereof.

<FIG> illustrates architecture of a system <NUM> of a network in accordance with some embodiments. The system <NUM> is shown to include a user equipment (UE) <NUM> and a UE <NUM>. The UEs <NUM> and <NUM> are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, or any computing device including a wireless communications interface.

In some embodiments, any of the UEs <NUM> and <NUM> can comprise an Internet of Things (IoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short-lived UE connections. An IoT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or loT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network describes interconnecting loT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The loT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the loT network.

The UEs <NUM> and <NUM> may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) <NUM> - the RAN <NUM> may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a Ne8Gen RAN (NG RAN), or some other type of RAN. The UEs <NUM> and <NUM> utilize connections <NUM> and <NUM>, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections <NUM> and <NUM> are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth generation (<NUM>) protocol, a New Radio (NR) protocol, and the like.

Four Quadrature Phase Shift Keying (QPSK) symbols may be mapped to each REG The PDCCH can be transmitted using one or more CCEs, depending on the size of the downlink control information (DCI) and the channel condition.

Some embodiments may use concepts for resource allocation for control channel information that are an e8ension of the above-described concepts. For example, some embodiments may utilize an enhanced physical downlink control channel (EPDCCH) that uses PDSCH resources for control information transmission. The EPDCCH may be transmitted using one or more enhanced the control channel elements (ECCEs). Similar to above, each ECCE may correspond to nine sets of four physical resource elements known as an enhanced resource element groups (EREGs). An ECCE may have other numbers of EREGs in some situations.

The RAN <NUM> is shown to be communicatively coupled to a core network (CN) <NUM> -via an S1 interface <NUM>. In embodiments, the CN <NUM> may be an evolved packet core (EPC) network, a Next Gen Packet Core (NPC) network, or some other type of CN. In this embodiment the S1 interface <NUM> is split into two parts: the S1-U interface <NUM>, which carries traffic data between the RAN nodes <NUM> and <NUM> and the serving gateway (S-GW) <NUM>, and the S1-mobility management entity (MME) interface <NUM>, which is a signaling interface between the RAN nodes <NUM> and <NUM> and MMEs <NUM>.

<FIG> illustrates example components of a device <NUM> in accordance with some embodiments. In some embodiments, the device <NUM> may include application circuitry <NUM>, baseband circuitry <NUM>, Radio Frequency (RF) circuitry <NUM>, front-end module (FEM) circuitry <NUM>, one or more antennas <NUM>, and power management circuitry (PMC) <NUM> coupled together at least as shown. The components of the illustrated device <NUM> may be included in a UE or a RAN node. In some embodiments, the device <NUM> may include less elements (e.g., a RAN node may not utilize application circuitry <NUM>, and instead include a processor/controller to process IP data received from an EPC). In some embodiments, the device <NUM> may include additional elements such as, for example, memory/storage, display, camera, sensor, or input/output (I/O) interface. In other embodiments, the components described below may be included in more than one device (e.g., said circuitries may be separately included in more than one device for Cloud-RAN (C-RAN) implementations).

The baseband circuitry <NUM> may include one or more baseband processors or control logic to process baseband signals received from a receive signal path of the RF circuitry <NUM> and to generate baseband signals for a transmit signal path of the RF circuitry <NUM>. Baseband processing circuity <NUM> may interface with the application circuitry <NUM> for generation and processing of the baseband signals and for controlling operations of the RF circuitry <NUM>. For example, in some embodiments, the baseband circuitry <NUM> may include a third generation (<NUM>) baseband processor 1804A, a fourth generation (<NUM>) baseband processor 1804B, a fifth generation (<NUM>) baseband processor 1804C, or other baseband processor(s) 1804D for other existing generations, generations in development or to be developed in the future (e.g., second generation (<NUM>), sixth generation (<NUM>), etc.). The baseband circuitry <NUM> (e.g., one or more of baseband processors 1804A-D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry <NUM>. In other embodiments, some or all of the functionality of baseband processors 1804A-D may be included in modules stored in the memory <NUM> and executed via a Central Processing Unit (CPU) 1804E. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry <NUM> may include Fast-Fourier Transform (FFT), precoding, or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry <NUM> may include convolution, tail-biting convolution, turbo, Viterbi, or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry <NUM> may include one or more audio digital signal processor(s) (DSP) 1804F. The audio DSP(s) 1804F may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry <NUM> and the application circuitry <NUM> may be implemented together such as, for example, on a system on a chip (SOC).

In some embodiments, the receive signal path of the RF circuitry <NUM> may include mixer circuitry 1806a, amplifier circuitry 1806b and filter circuitry 1806c. In some embodiments, the transmit signal path of the RF circuitry <NUM> may include filter circuitry 1806c and mixer circuitry 1806a. RF circuitry <NUM> may also include synthesizer circuitry 1806d for synthesizing a frequency for use by the mixer circuitry 1806a of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 1806a of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry <NUM> based on the synthesized frequency provided by synthesizer circuitry 1806d. The amplifier circuitry 1806b may be configured to amplify the down-converted signals and the filter circuitry 1806c may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry <NUM> for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a necessity. In some embodiments, mixer circuitry 1806a of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 1806a of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 1806d to generate RF output signals for the FEM circuitry <NUM>. The baseband signals may be provided by the baseband circuitry <NUM> and may be filtered by filter circuitry 1806c.

In some embodiments, the mixer circuitry 1806a of the receive signal path and the mixer circuitry 1806a of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and upconversion, respectively. In some embodiments, the mixer circuitry 1806a of the receive signal path and the mixer circuitry 1806a of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 1806a of the receive signal path and the mixer circuitry 1806a may be arranged for direct downconversion and direct upconversion, respectively. In some embodiments, the mixer circuitry 1806a of the receive signal path and the mixer circuitry 1806a of the transmit signal path may be configured for super-heterodyne operation.

In some embodiments, the synthesizer circuitry 1806d may be a fractional-N synthesizer or a fractional N/N+<NUM> synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 1806d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

The synthesizer circuitry 1806d may be configured to synthesize an output frequency for use by the mixer circuitry 1806a of the RF circuitry <NUM> based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 1806d may be a fractional N/N+<NUM> synthesizer.

In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a necessity.

Synthesizer circuitry 1806d of the RF circuitry <NUM> may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+<NUM> (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 1806d may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry <NUM> may include an IQ/polar converter.

While <FIG> shows the PMC <NUM> coupled only with the baseband circuitry <NUM>. However, in other embodiments, the PMC <NUM> may be additionally or alternatively coupled with, and perform similar power management operations for, other components such as, but not limited to, application circuitry <NUM>, RF circuitry <NUM>, or FEM <NUM>.

If there is no data traffic activity for an extended period of time, then the device <NUM> may transition off to an RRC_Idle state, where it disconnects from the network and does not perform operations such as channel quality feedback, handover, etc. The device <NUM> goes into a very low power state and it performs paging where again it periodically wakes up to listen to the network and then powers down again. The device <NUM> may not receive data in this state, in order to receive data, it can transition back to RRC_Connected state.

<FIG> illustrates example interfaces of baseband circuitry in accordance with some embodiments. As discussed above, the baseband circuitry <NUM> of <FIG> may comprise processors 1804A-1804E and a memory <NUM> utilized by said processors. Each of the processors 1804A-1804E may include a memory interface, 1904A-1904E, respectively, to send/receive data to/from the memory <NUM>.

<FIG> provides an example illustration of the wireless device, such as a user equipment (UE), a mobile station (MS), a mobile wireless device, a mobile communication device, a tablet, a handset, or other type of wireless device. The wireless device can include one or more antennas configured to communicate with a node, macro node, low power node (LPN), or, transmission station, such as a base station (BS), an evolved Node B (eNB), a baseband processing unit (BBU), a remote radio head (RRH), a remote radio equipment (RRE), a relay station (RS), a radio equipment (RE), or other type of wireless wide area network (WWAN) access point. The wireless device can be configured to communicate using at least one wireless communication standard such as, but not limited to, 3GPP LTE, WiMAX, High Speed Packet Access (HSPA), Bluetooth, and WiFi. The wireless device can communicate using separate antennas for each wireless communication standard or shared antennas for multiple wireless communication standards. The wireless device can communicate in a wireless local area network (WLAN), a wireless personal area network (WPAN), and/or a WWAN. The wireless device can also comprise a wireless modem. The wireless modem can comprise, for example, a wireless radio transceiver and baseband circuitry (e.g., a baseband processor). The wireless modem can, in one example, modulate signals that the wireless device transmits via the one or more antennas and demodulate signals that the wireless device receives via the one or more antennas.

<FIG> also provides an illustration of a microphone and one or more speakers that can be used for audio input and output from the wireless device. The display screen can be a liquid crystal display (LCD) screen, or other type of display screen such as an organic light emitting diode (OLED) display. The display screen can be configured as a touch screen. The touch screen can use capacitive, resistive, or another type of touch screen technology. An application processor and a graphics processor can be coupled to internal memory to provide processing and display capabilities. A non-volatile memory port can also be used to provide data input/output options to a user. The non-volatile memory port can also be used to expand the memory capabilities of the wireless device. A keyboard can be integrated with the wireless device or wirelessly connected to the wireless device to provide additional user input. A virtual keyboard can also be provided using the touch screen.

Various techniques, or certain aspects or portions thereof, may take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, compact disc-read-only memory (CD-ROMs), hard drives, non-transitory computer readable storage medium, or any other machine-readable storage medium wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for practicing the various techniques. In the case of program code execution on programmable computers, the computing device may include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. The volatile and non-volatile memory and/or storage elements may be a random-access memory (RAM), erasable programmable read only memory (EPROM), flash drive, optical drive, magnetic hard drive, solid state drive, or other medium for storing electronic data. The node and wireless device may also include a transceiver module (i.e., transceiver), a counter module (i.e., counter), a processing module (i.e., processor), and/or a clock module (i.e., clock) or timer module (i.e., timer). In one example, selected components of the transceiver module can be located in a cloud radio access network (C-RAN). One or more programs that may implement or utilize the various techniques described herein may use an application programming interface (API), reusable controls, and the like. Such programs may be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) may be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language, and combined with hardware implementations.

It should be understood that many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom very-large-scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components.

Modules may also be implemented in software for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module may not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module.

Indeed, a module of executable code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. The modules may be passive or active, including agents operable to perform desired functions.

Reference throughout this specification to "an example" or "exemplary" means that a particular feature, structure, or characteristic described in connection with the example is included in at least one embodiment of the present technology. Thus, appearances of the phrases "in an example" or the word "exemplary" in various places throughout this specification are not necessarily all referring to the same embodiment.

In addition, various embodiments and example of the present technology may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as defacto equivalents of one another, but are to be considered as separate and autonomous representations of the present technology.

Claim 1:
An apparatus of a base station that is operable to use phase tracking reference signals, PT-RS, the apparatus comprising:
one or more processors configured to:
identify a modulation and coding scheme, MCS, for a UE for a bandwidth part, BWP, with a subcarrier spacing, SCS;
select a time density of the PT-RS based on the MCS;
select a frequency density of the PT-RS based on an allocated bandwidth in the BWP; and
encode the time density and the frequency density for the PT- RS in higher layer signaling for transmission to the UE; and
a memory interface configured to send to a memory the time density based on the MCS, and frequency density based on the allocated bandwidth.