Abstract:
Method and apparatus for bridging wired and wireless communication networks are disclosed. The method includes interfacing with a wired communication network, and interfacing with a wireless communication network, where the wired communication network and the wireless communication network have different communication media for transmitting communication signals, and the wired communication network and the wireless communication network use different communication protocols for transmitting the communication signals. The method further includes detecting the different communication protocols of the communication signals, programming a baseband processing module for transmitting the communication signals between the different communication protocols and the different communication media dynamically, and bridging communication signals between the wired communication network and the wireless communication network using the baseband processing module.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of communication networks. In particular, the present invention relates to a method and apparatus for bridging wired and wireless communication networks. 
       BACKGROUND OF THE INVENTION 
       [0002]    In recent years, mobile devices, such as cellular phones and portable personal digital assistances (PDAs), have been widely adopted to assist people to communicate with each other while they are traveling. There are various protocols based on OFDM or a variation of OFDM used for communication of information among users. For example, there are WiFi, WiMAX, DVB-T/H/S, DMB for wireless communication networks and digital subscriber line (DSL), Power line, DOCSIS for wired communication networks. The advantage of OFDM based protocol is that the signal is resilient in a multi-path environment such as in a mobile communication situation or an urban environment. However, the wired communication network and wireless communication network are not interoperable because of the different communication media and because of the different communication protocols used in transmitting and receiving communication signals in the wired and wireless communication networks. In other words, if one device uses one communication medium such as the cable line and another device uses another communication medium such as the satellite, these two devices can not communicate with each other from the cable line to the satellite or vice versa. Similarly, if one device uses one communication protocol such as the DOCSIS and another device uses another communication protocol such as the WiMAX, these two devices can not communicate with each other because of the differences in the communication protocols used by the two devices. 
         [0003]    To address this problem, conventional methods build dedicated hardware and software systems to bridge one specific medium to another specific medium, such as from the phone line to the satellite transmission of cellular signals for cellular phones. The conventional methods also implement dedicated hardware and software systems to communicate between specific protocols, such as from DOCSIS to WiMAX. However, because such systems rely on dedicated hardware and software implementations to provide point-to-point solutions, they are not scalable to cover new communication media or new communication protocols. As a result, such conventional systems may not work for both North America and Asia because of the different communication media and protocols used in the two different regions. 
         [0004]    Therefore, there is a need for a method and apparatus that can bridge between wired and wireless communication networks for multiple communication media and multiple communication protocols. 
       SUMMARY 
       [0005]    The present invention relates to a method and apparatus for bridging wired and wireless communication networks. The invention supports data communications between multiple communication media, multiple communication protocols, and multiple system interfaces. This is accomplished by using a reconfigurable and processing sharing technique that extracts variations of protocol, medium, and interface processing into a reconfiguration baseband processing module, and using an intelligent controller to dynamically configure the baseband processing module in accordance with the requirements of the incoming and outgoing communication signals in the wired and wireless communication networks. 
         [0006]    In one embodiment, an apparatus for bridging wired and wireless communication networks includes a first network interface configured to interface with a wired communication network, and a second network interface configured to interface with a wireless communication network, where the wired communication network and the wireless communication network have different communication media for transmitting communication signals and the wired communication network and the wireless communication network use different communication protocols for transmitting the communication signals. The apparatus further includes a baseband processing module configured to bridge communication signals between the first network interface and the second network interface, and a controller configured to detect the different communication protocols of the communication signals and to program the baseband processing module dynamically for transmitting the communication signals between the different communication protocols and the different communication media. 
         [0007]    In another embodiment, a method for bridging wired and wireless communication networks includes interfacing with a wired communication network, and interfacing with a wireless communication network, where the wired communication network and the wireless communication network have different communication media for transmitting communication signals, and the wired communication network and the wireless communication network use different communication protocols for transmitting the communication signals. The method further includes detecting the different communication protocols of the communication signals, programming a baseband processing module for transmitting the communication signals between the different communication protocols and the different communication media dynamically, and bridging communication signals between the wired communication network and the wireless communication network using the baseband processing module. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The aforementioned features and advantages of the invention, as well as additional features and advantages thereof, will be more clearly understandable after reading detailed descriptions of embodiments of the invention in conjunction with the following drawings. 
           [0009]      FIG. 1  illustrates an application of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0010]      FIG. 2  illustrates a block diagram of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0011]      FIG. 3  illustrates interactions between the controller and the baseband processing module of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0012]      FIG. 4  illustrates a block diagram of the baseband processing module of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0013]      FIG. 5  illustrates a block diagram of the controller of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0014]      FIG. 6  illustrates a flow diagram for the controller of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0015]      FIG. 7  illustrates an application of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0016]      FIG. 8  illustrates another application of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0017]      FIG. 9  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0018]      FIG. 10  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. 
           [0019]      FIG. 11  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. 
       
    
    
       [0020]    Like numbers are used throughout the figures. 
       DESCRIPTION OF EMBODIMENTS 
       [0021]    Method and apparatus are provided for bridging wired and wireless communication networks. The following descriptions are presented to enable any person skilled in the art to make and use the invention. Descriptions of specific embodiments and applications are provided only as examples. Various modifications and combinations of the examples described herein will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other examples and applications without departing from the spirit and scope of the invention. Thus, the present invention is not intended to be limited to the examples described and shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. 
         [0022]    Some portions of the detailed description that follows are presented in terms of flowcharts, logic blocks, and other symbolic representations of operations on information that can be performed on a computer system. A procedure, computer-executed step, logic block, process, etc., is here conceived to be a self-consistent sequence of one or more steps or instructions leading to a desired result. The steps are those utilizing physical manipulations of physical quantities. These quantities can take the form of electrical, magnetic, or radio signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. These signals may be referred to at times as bits, values, elements, symbols, characters, terms, numbers, or the like. Each step may be performed by hardware, software, firmware, or combinations thereof. 
         [0023]      FIG. 1  illustrates an application of the wire-wireless bridge device according to an embodiment of the present invention. As shown in  FIG. 1 , a wire-wireless bridge  12  is used to communicate between a wired communication network  11  and a wireless communication network  12 . In this example, a communication from the wired communication network  111  to the wireless communication network  13  may be conducted as follows. A first incoming communication signal is received through one or more wired communication means  14 . After the first incoming communication signal is received and processed by the wire-wireless bridge  12 , it is transmitted to the wireless communication network through one or more wireless communication means  16  to the wireless communication network  13 . Similarly, a communication from the wireless communication network  13  to the wired communication network  11  may be conducted as follows. A second incoming communication signal is received through one or more wireless communication means  17 . After the second incoming communication signal is received and processed by the wire-wireless bridge  12 , it is transmitted to the wireless communication network through one or more wired communication means  15  to the wired communication network  11 . 
         [0024]    Note that in different embodiments of the present invention, the one or more wired communication means  14  and  15  may share the same medium or may use different media, such as digital subscriber line (DSL), Ethernet, cable, phone line, or power line. In addition, the one or more wireless communication means  16  and  17  may share the same medium or may use different media, such as satellite or terrestrial transmission. 
         [0025]      FIG. 2  illustrates a block diagram of the wire-wireless bridge device according to an embodiment of the present invention. In the example shown in  FIG. 2 , the wire-wireless bridge device includes a baseband processing module  20  and a controller unit  21 . In addition, on the wireless network communication side, the wire-wireless bridge device includes a wireless network interface  2 , an amplifier (AMP)  3 , an automatic gain control unit (AGC)  4 , and an analog-to-digital/digital-to-analog (AD/DA) converter or transmitter-receiver (TX/RX)  5 . On the wired communication network side, the wire-wireless bridge device further includes a wired network interface  6 , an amplifier (AMP)  8 , an automatic gain control unit (AGC)  9 , and an analog-to-digital/digital-to-analog (AD/DA) converter or transmitter/receiver (TX/RX)  10 . 
         [0026]    The wireless network interface  2  receives and transmits wireless signals from and to multiple wireless sources through wireless media represented by the numeral  1 . Similarly, the wired network interface  6  receives and transmits wired signals from and to multiple wired sources through wired media represented by the numeral  7 . 
         [0027]    For example, the wire-wireless bridge device  12  may be configured to receive signals encoded in multiple wired protocols. First, a communication signal from a wired network is received by the wired network interface  6 , which delivers the signal to the AD/DA converter  5  via the AGC  9 . The AGC  9  controls the gain of the wire-wireless bridge device in order to maintain adequate performance over a range of input signal levels. Next, the AD/DA converter  5  delivers a converted digital signal to the baseband processing module  20  and to the controller  21 . The controller  21  analyzes the incoming signal to determine the communication protocol of the incoming signal. The controller retrieves a set of configuration parameters and binary codes for configuring the baseband processing module  20  in accordance with the communication protocol of the incoming signal. The controller  21  configures the baseband processing module  20  using the set of configuration parameters and binary codes. Next, after the baseband processing module  20  is configured, it processes the incoming digital signal using one or more of the predetermined communication protocols, for example FFT, channel decode, de-framing, and error correction, to decode the received data content form the incoming signal. Afterwards, the decoded data content is delivered to the high level (MAC layer  32 ) to be further processed to obtain the application data, which is also referred to as the application payload, for further processing by the application layer above. 
         [0028]    For another example, the wire-wireless bridge device  12  may be configured to transmit signals encoded in multiple wireless protocols. First, the media access control (MAC) layer of the software application  32  receives and processes an application payload, and creates communication packets for transmission. The communication packets are then delivered to the baseband processing module  20 . Next, the controller  21  is notified by MAC layer  32  that a new protocol is to be processed in the baseband processing module  20 . The controller then retrieves a corresponding set of configuration parameters and binary codes for the new protocol, and configures the baseband processing module  20  using the set of configuration parameters and binary codes. Then, after the baseband processing module  20  being configured by the controller, it processes the incoming digital signal using one or more of the predetermined OFDM based communication protocols, such as channel encode, framing, IFFT to decode the received baseband signal to be sent to the AD/DA converter  5 . Afterwards, the AD/DA converter  5  delivers a converted analog signal to the wireless network interface  2  via an amplifier  3 . The wireless network interface  2  modulates the signal to proper carrier frequency and transmits it over antenna to a wireless communication network. 
         [0029]    For yet another example, the wire-wireless bridge device  12  may be configured to bridge between multiple communication protocols between the wired communication network  11  and the wireless communication network  13 . In this case the device of  FIG. 5  is used to bridge two protocols. In other words, the protocol coming from the wired interface may be converted to the wireless protocol. First, the method for receiving signals encoded in multiple wired protocols described above is repeated to obtain the application payload of the incoming signal at the MAC layer  22 . Next, the result of MAC layer  32 , instead of delivered to a software application at a higher layer, is again processed at the MAC layer according to the outbound protocol. The processed data is then delivered to the baseband processing module  20 . The controller  21  is notified by MAC layer  32  that a new processing protocol is to be performed at the baseband processing module  20 . The controller retrieves a set of configuration parameters and binary codes for the new protocol and configures the baseband processing module  20  using the set of configuration parameters and binary codes accordingly. After the baseband processing module  20  being configured by the controller  21 , it processes the digital signal using one or more of the predetermined OFDM based communication protocols, such as channel encode, framing, IFFT to decode the baseband signal to be sent to the AD/DA converter  5 . Afterwards, the AD/DA converter  5  delivers a converted analog signal to the wireless network interface  2  via an amplifier  3 . The wireless network interface  2  modulates the signal to proper carrier frequency and transmits it over antenna to a wireless communication network. 
         [0030]    Note that in order to handle multiple communication protocols and multiple communication media for both the wired and wireless communication networks, the controller  21  is capable of dynamically configuring the baseband processing module  20  of the wire-wireless bridge device according to the protocols and media of the communication signals received and transmitted. 
         [0031]      FIG. 3  illustrates an implementation of the controller and the baseband processing module of the wire-wireless bridge device according to an embodiment of the present invention. In various embodiments of the present invention, transactions between the baseband processing module  20  and the controller  20  may implement a standardized interface so that any implementation of the baseband processing module and the controller that comply with the standard interface may work with each other. In one implementation, the baseband processing module  20  may be implemented with a combination of digital signal processor (DSP)  23  and a field programmable gate array (FPGA)  24 . The controller  21  may be implemented with a 32-bit central processing unit (CPU)  25  and a memory storage device  26 . 
         [0032]      FIG. 4  illustrates a block diagram of the baseband processing module of the wire-wireless bridge device according to an embodiment of the present invention. As described above, the baseband processing module  20  may be configured and/or reconfigured with programmable parameters and/or binary codes to handle any specific communication protocols and media. When a new protocol is to be processed at baseband level, programmable parameters corresponding to the new protocol are set by the controller  21 . Proper binary codes are downloaded to the baseband processing module  20  if necessary. After the configuration process, the baseband processing module  20  may process the new protocol. 
         [0033]    As shown in  FIG. 4 , the baseband processing module  20  includes a channel estimation module  35 , a channel compensation module  36 , a fast Fourier transform (FFT/IFFT) module  37 , a channel coding module  38 , a framing-deframing module  39 , and a mapping module  40  in various embodiments of the present invention. The channel estimation module  35  estimates the noise level and distortion level of the communication media through which the signal travels. The channel compensation module  36  compensates the received signal (in terms of amplitude and phase of the sampled analog signal) according to the outcome of the channel estimation previously performed. The FFT/IFFT module  37  converts signals between frequency domain and time domain, which may be required by the OFDM-based communication protocols. The channel coding module  38  encodes/decodes the baseband signals (in terms of bits) so that if any bit error occurs due to a noisy environment, it can be corrected. The channel coding module  38  implements one or more channel coding algorithms, such as interleaving, forward error correction (Viterbi, Turbo, Reed Solomon, etc.). The framing-deframing module  39  partitions a continuous bit stream into frames and insert markers or pilots into each frame for channel estimation and for other purposes during transmission of a communication signal. In addition, the framing-deframing module  39  removes previously inserted markers or pilots, and reassembles the frames back to a continuous bit stream during receiving of the communication signal. The mapping module  40  maps groups of bits, for example a group of 4 bits, into symbols as defined by a modulation technique (e.g. QAM16). 
         [0034]    Note that each module in the baseband processing module  20  may be configured with parameters as required by a specific protocol. For example, when 802.11a protocol is selected, the FFT/IFFT module  37  may be configured as a 64-point FFT/IFFT; when WiMAX protocol is selected, the FFT/IFFT module  37  may be configured as a 256-point FFT/IFFT. Moreover, when the Reed-Solomon algorithm is employed for channel coding, there are two parameters that need to be configured: 1) the number of total symbols (n), including both data symbols and error correction symbols, per coding block, and 2) the number of data symbols per block (k). These two parameters may vary depending on the specific communication protocol of the signal to be processed. When a protocol is selected, the controller  21  configures the channel coding module to perform the Reed-Solomon algorithm with proper parameters n and k. Furthermore, the framing and deframing module  39  is also configured by the controller  21  with parameters such as pilot size, preamble size, etc. according to the different communication protocols being implemented. 
         [0035]    In addition to configuring the parameters of a module, binary codes of the module may be replaced for processing new protocols in alternative implementations. Binary codes (or microcodes) are the instruction set that provide instructions to a module. This is done by downloading new binary codes to the module corresponding to a new communication protocol to be implemented. In some cases, this may be accomplished by configuring parameters of a module. In some other cases, this may be accomplished by downloading new binary codes to configure the module. 
         [0036]      FIG. 5  illustrates a block diagram of the controller of the wire-wireless bridge device according to an embodiment of the present invention. In the example shown in  FIG. 5 , the controller  21  includes a protocol analyzer module  27 , a signal protocol selection module  28 , a protocol parameter and binary code repository module, a baseband configuration module  30 , and a radio-frequency (RF) interface switch module  31 . The protocol analyzer module  27  receives signals from multiple RF interfaces and analyzes the received signals to determine a corresponding communication protocol to be implemented. The signal protocol selection module  28  selects a protocol to be implemented by one of the two inputs: 1) obtain an interactive command from a user (for example, a user may press a button “802.11a”, which means that the 802.11a protocol is selected); or 2) obtain a command from the protocol analyzer  27 . The protocol parameter and binary code repository module  29  store the configuration parameters and binary codes to be used for the baseband processing module  20 . The baseband configuration module  30  configures the baseband processing module  20  with proper parameters and binary codes based on a protocol selected by the signal protocol selection module  28 . The RF interface switch module  31  connects one of the multiple RF interfaces with the baseband processing module  20 . 
         [0037]      FIG. 6  illustrates a flow diagram for the controller of the wire-wireless bridge device according to an embodiment of the present invention. The method starts in block  61  and thereinafter moves to block  62 . In block  62 , the controller waits for a user input to select a protocol or select a protocol corresponding to an RF interface that has a data input. In step  63 , the controller retrieves the parameters and binary codes corresponding to the selected protocol from a database. In block  64 , the controller configures the baseband processing module using the parameters and binary codes retrieved. In block  65 , the controller connects the RF interface corresponding to the selected protocol with the baseband processing module. After block  65 , the baseband processing module is ready to process the selected protocol. The method ends in block  66 . 
         [0038]      FIG. 7  illustrates an application of the wire-wireless bridge device according to an embodiment of the present invention. As shown in  FIG. 7 , the system includes a wire-wireless bridge  70  as a central hub for communication with various wired and wireless communication devices implementing the fourth generation wireless communication technology. The system further includes connections to a router  85 , a cellular phone  71 , a cellular tower  72 , a base station demonstration kit  73 , a television  74 , a video camera  75 , a land line phone  76 , a gas sensor  77 , a laptop computer as a demonstration monitor, a router  79  that connects to the Internet  80 , a digital TV server  81 , a server  82  for monitoring mine safety, and a GPS navigation system  83  that communicates with a satellite  84 . 
         [0039]      FIG. 8  illustrates another application of the wire-wireless bridge device according to an embodiment of the present invention. In this example, the system includes a wire-wireless bridge  90  as a central hub for communication with various wired and wireless communication devices in a security application. The system further includes multiple video cameras for monitoring various locations and activities, a server  92  that communicates with a city monitoring center  93  and a security monitoring center  94 , and the server also communicates with police cars  96  via 3G/4G wireless communication technologies  95 . 
         [0040]      FIG. 9  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. In the example shown in  FIG. 9 , the system includes a wire-wireless bridge  100  as a central hub for communication with various wired and wireless communication devices in a mine safety monitoring application. The system further includes a remote mine office  101 , a mine tunnel  102 , a power line  103 , an underground video monitor  104 , a gas sensor  105 , and a phone  106 . The wire-wireless bridge communicates conditions in the mine tunnel to a monitor center  108  via a satellite  107 . 
         [0041]      FIG. 10  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. As shown in  FIG. 10 , the system includes a wire-wireless bridge  110  as a central hub for communication with various wired and wireless communication devices in a traffic monitoring application. The systems further includes multiple routers that directs traffic information from street intersections  112 , from railway crossings  113 , and from tunnels  114 , a server  118  in a control center that transmits the traffic information to various receiver terminals, such as a car  116  and a bus  117 . A user in the car is able to view a picture of a particular traffic location of her interest using her cellular phone  119 . 
         [0042]      FIG. 11  illustrates yet another application of the wire-wireless bridge device according to an embodiment of the present invention. In this example, the system includes multiple wire-wireless bridges  120 ,  123 , and  125  as means for communication with various wired and wireless communication devices using power lines. The system further includes a cellular phone base station  121 , a 10 KVAC MV power line  122 , a satellite dish  124 , a 220/380 VAC LV power line  126 , a video surveillance camera  127 , multiple rural houses  131  with each house having a phone  132 , a personal computer  133 , and an adaptive multi-rate (AMR) device coupled to the power line connecting to each of the houses. 
         [0043]    It will be appreciated that the above description for clarity has described embodiments of the invention with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units or processors may be used without detracting from the invention. For example, functionality illustrated to be performed by separate processors or controllers may be performed by the same processors or controllers. Hence, references to specific functional units are to be seen as references to suitable means for providing the described functionality rather than indicative of a strict logical or physical structure or organization. 
         [0044]    The invention can be implemented in any suitable form, including hardware, software, firmware, or any combination of these. The invention may optionally be implemented partly as computer software running on one or more data processors and/or digital signal processors. The elements and components of an embodiment of the invention may be physically, functionally, and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units, or as part of other functional units. As such, the invention may be implemented in a single unit or may be physically and functionally distributed between different units and processors. 
         [0045]    One skilled in the relevant art will recognize that many possible modifications and combinations of the disclosed embodiments may be used, while still employing the same basic underlying mechanisms and methodologies. The foregoing description, for purposes of explanation, has been written with references to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described to explain the principles of the invention and their practical applications, and to enable others skilled in the art to best utilize the invention and various embodiments with various modifications as suited to the particular use contemplated.