PATENT DOCUMENT

Publication Number: US-9083496-B2
Application Number: US-201113136489-A
Country: US
Kind Code: B2

Title: Adaptive antenna system signal detection

Abstract:
A system and method for processing signals in a communication system is disclosed herein. The system and method comprises processing steps and processing logic for generating a downlink subframe comprising a preamble and a plurality of data bursts within a predetermined frequency band; embedding first and second sets of downlink subframe parameters in the downlink subframe; transmitting the downlink subframe; receiving the downlink subframe; processing data in the preamble to obtain channel quality indicator (CQI) information; and using the CQI information to select either the first set or set second set of downlink subframe parameters to process the data bursts in the downlink subframe.

Claims:
What is claimed is: 
     
       1. A method of processing signals in a communication system, comprising:
 receiving a downlink subframe within a predetermined frequency band, wherein the downlink subframe is one of two or more downlink subframes comprised in a downlink frame; 
 decoding one or more portions of the downlink subframe; 
 determining a relative channel quality responsive to decoding the one or more portions of the downlink subframe; 
 when the relative channel quality meets a threshold criterion:
 searching all scannable frequencies within said frequency band for adaptive antenna system (AAS) parameters; and 
 subsequently searching all scannable frequencies in said frequency band for channel parameters when no AAS parameters are detected; and 
 
 decoding a data burst in accordance with the AAS parameters or channel parameters. 
 
     
     
       2. The method of  claim 1 , further comprising selecting a channel parameters when said relative channel quality does not meet said criterion. 
     
     
       3. The method of  claim 1 , wherein the one or more portions of the downlink subframe comprise a preamble. 
     
     
       4. The method of  claim 3 , wherein the relative channel quality is indicated with a channel quality indication (CQI). 
     
     
       5. The method of  claim 3 , wherein the relative channel quality is indicated with a Carrier to Interference plus Noise Ratio (CINR). 
     
     
       6. The method of  claim 3 , wherein the relative channel quality is indicated with a Signal to Noise Ratio (SNR). 
     
     
       7. The method of  claim 1 , wherein the downlink subframe comprises a set of AAS parameters and a set of channel parameters. 
     
     
       8. The method of  claim 7 , wherein the first set of data comprises a set of adaptive antenna system (AAS) parameters. 
     
     
       9. The method of  claim 7 , wherein the second set of data comprises a set of channel parameters. 
     
     
       10. The method of  claim 1 , wherein the downlink subframe comprises only one of the AAS parameters and the channel parameters. 
     
     
       11. A wireless communication device, comprising:
 a wireless interface configured to communicate with a serving apparatus; 
 a processor; and 
 a computer readable apparatus having a storage medium with at least one computer program stored thereon, the at least one computer program configured to, when executed on the processor:
 determine a relative channel quality according to one or more portions of a downlink subframe, wherein the downlink subframe is one of two or more downlink subframes comprised in a downlink frame; 
 when the relative channel quality meets a threshold criterion:
 searching all scannable frequencies within said frequency band for AAS (adaptive antenna system) parameters; and 
 subsequently searching all scannable frequencies in said frequency band for channel parameters when no AAS parameters are detected; and 
 
 decode a data burst in accordance with the AAS parameters or channel parameters. 
 
 
     
     
       12. The wireless communication device of  claim 11 , wherein the computer program is additionally configured to, when executed by the processor, receive the downlink subframe. 
     
     
       13. The wireless communication device of  claim 12 , wherein the downlink subframe comprises at least a preamble. 
     
     
       14. The wireless communication device of  claim 13 , wherein the relative channel quality is determined by decoding the preamble. 
     
     
       15. The wireless communication device of  claim 13 , wherein the downlink subframe comprises the AAS and channel parameters. 
     
     
       16. The wireless communication device of  claim 15 , wherein the AAS parameters comprises a set of AAS parameters. 
     
     
       17. The wireless communication device of  claim 15 , wherein the channel parameters comprises a set of channel parameters.

Description:
PRIORITY 
     This application is a continuation of and claims priority to co-owned co-pending U.S. patent application Ser. No. 11/830,458 of the same title filed Jul. 30, 2007, the foregoing incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is directed in general to the field of information processing. In one aspect, the present invention relates to a system and method for improving efficiency in communication networks employing adaptive antenna systems. 
     2. Description of the Related Art 
     Wireless communication systems transmit and receive signals within a designated electromagnetic frequency spectrum, but the capacity of the electromagnetic frequency spectrum is limited. As the demand for wireless communication systems continues to expand, there are increasing challenges to improve spectrum usage efficiency. To address this problem, many communication networks have been designed to support adaptive antenna systems (AAS) to improve the communication capacity of the network. Adaptive antenna systems comprise multiple antennas at the transmitting and/or the receiving side of the communication link. In communication networks supporting AAS, the signals are processed adaptively to exploit the spatial dimension of the communication channel. 
       FIG. 1  depicts a wireless communication system  100  in which a transmitter  102  having a single antenna or an array of antennas  106  communicates with receiver  104  having a single antenna or an array of antennas  108 . The communication system  100  may be any type of wireless communication system including, but not limited to, a Multiple Input, Multiple Output (MEMO) system, a Space Division Multiple Access (SDMA) system, a Code Division Multiple Access (CDMA) system, an Orthogonal Frequency Division Multiplexing (OFDM) system, or an Orthogonal Frequency Division Multiple Access (OFDMA) system. In the communication system  100 , the transmitter  102  may act as a base station, while the receiver  104  acts as a subscriber station, which can be virtually any type of wireless one-way or two-way communication device such as a cellular telephone, wireless equipped computer system, and wireless personal digital assistant. The receiver/subscriber station  104  can also transmits signals which are received by the transmitter/base station  102 . The signals communicated between transmitter  102  and receiver  104  can include voice, data, electronic mail, video, and other data, voice, and video signals. In operation, the transmitter  102  transmits a signal data stream (e.g., signal s 1 ) through one or more antennas  106  and over a channel H 1  to a receiver  104 , which combines the received signal from one or more receive antennas  108  to reconstruct the transmitted data. To transmit the signal vector s 1 , the transmitter  102  prepares a transmission signal, represented by the vector x 1 , for the signal s 1 . (Note: lower case bold variables indicate vectors and upper case BOLD variables indicate matrices). The transmission signal vector x 1  is transmitted via a channel represented by a channel matrix H 1 , and is received at the receiver  104  as a receive signal vector y 1 =H 1 x 1 +n 1  (where n represents co-channel interference or noise). The channel matrix H 1  represents a channel gain between the transmitter antenna array  106  and the subscriber station antenna array  108 . Thus, the channel matrix H 1  can be represented by a k×N matrix of complex coefficients, where N is the number of antennas in the transmitter/base station antenna array  106  and k is the number of antennas in the receiver/subscriber station antenna array  108 . The value of k can be unique for each receiver/subscriber station. As will be appreciated, the channel matrix H 1  can instead be represented by a N×k matrix of complex coefficients, in which case the matrix manipulation algorithms are adjusted accordingly so that, for example, the right singular vector calculation on a k×N channel matrix becomes a left singular vector calculation on a N×k channel matrix. The coefficients of the channel matrix H 1  depend, at least in part, on the transmission characteristics of the medium, such as air, through which a signal is transmitted. A variety of methods may be used at the receiver to determine the channel matrix H 1  coefficients, such as transmitting a known pilot signal to a receiver so that the receiver, knowing the pilot signal, can estimate the coefficients of the channel matrix H 1  using well-known pilot estimation techniques. Alternatively, when the channel between the transmitter and receiver are reciprocal in both directions, the actual channel matrix H 1  is known to the receiver and may also be known to the transmitter. 
     Communication networks that support AAS do not necessarily provide AAS support in all of the cells of the network. When a subscriber set is operating in a non-AAS cell, it must scan all allocated frequencies to decode channel parameters. If, however, the subscriber set is in an AAS cell, it cannot receive channel parameters and, therefore, must scan all allocated frequencies to decode AAS parameters. Currently, subscribers scan all allocated frequencies to attempt to decode both channel parameters and AAS parameters, even though only one of those sets of parameters is relevant based on the position of the subscriber set. Therefore, the subscriber set unnecessarily consumes significant processing resources. It is apparent, therefore, that there is a need for an improved system and method for scanning allocated frequencies to decode channel parameters and/or AAS parameters in communication networks that support AAS. 
     Further limitations and disadvantages of conventional processes and technologies will become apparent to one of skill in the art after reviewing the remainder of the present application with reference to the drawings and detailed description which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention may be understood, and its numerous objects, features and advantages obtained, when the following detailed description of a preferred embodiment is considered in conjunction with the following drawings, in which: 
         FIG. 1  (labeled prior art) depicts a wireless communication system. 
         FIG. 2  shows a communication system with a plurality of subscriber sets in non-AAS cells and AAS cells. 
         FIG. 3  depicts example downlink subframes used in a communication network that supports adaptive antenna systems. 
         FIG. 4  depicts a wireless communication system in which a plurality of subscriber sets are operable to use channel quality information to scan allocated frequencies for channel parameters and/or AAS parameters. 
         FIG. 5  is an illustration of data processing steps implemented in various embodiments of the invention. 
     
    
    
     It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the drawings have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements for purposes of promoting and improving clarity and understanding. Further, where considered appropriate, reference numerals have been repeated among the drawings to represent corresponding or analogous elements. 
     DETAILED DESCRIPTION 
     A system and methodology are disclosed for using channel quality indicators for scanning allocated frequencies to decode channel parameters and/or AAS parameters in communication networks that support AAS. Various illustrative embodiments of the present invention will now be described in detail with reference to the accompanying figures. While various details are set forth in the following description, it will be appreciated that the present invention may be practiced without these specific details, and that numerous implementation-specific decisions may be made to the invention described herein to achieve the device designer&#39;s specific goals, such as compliance with process technology or design-related constraints, which will vary from one implementation to another. While such a development effort might be complex and time-consuming, it would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. For example, selected aspects are shown in block diagram form, rather than in detail, in order to avoid limiting or obscuring the present invention. In addition, some portions of the detailed descriptions provided herein are presented in terms of algorithms or operations on data within a computer memory. Such descriptions and representations are used by those skilled in the art to describe and convey the substance of their work to others skilled in the art. 
       FIG. 2  is an illustration of a communication network  200  comprising a base station  202  that is operable to transmit to a plurality of subscribers in AAS cell  204  and non-AAS cell  206 . Subscribers  208  and  210  in AAS cell  204  cannot receive channel parameters and, therefore, must scan all allocated frequencies to decode AAS parameters. Subscribers  212  and  214  are in the non-AAS cell  206  and, therefore, are able to receive channel parameters. As discussed above, subscribers currently scan all allocated frequencies to attempt to decode both channel parameters and AAS parameters, thereby consuming significant processing resources. In various embodiments of the present invention, a channel quality indicator, such as carrier to interference-plus-noise ratio (CINR) is used to simplify the parameter search process. 
       FIG. 3  is an illustration of a downlink subframe used in a communication system that supports AAS. The subframe  300  shown in  FIG. 3  is a simplified version of a downlink subframe described in the IEEE 802.16 standard. A complete description of the downlink subframe used in the aforementioned standard can be found in Section 8.4.4.6 of IEEE 802.16-2005. Downlink subframe  300  comprises a preamble  302 , an uplink map  304 , a downlink map  306  and one or more diversity map zones  308 . The downlink subframe  300  further comprises a plurality of downlink bursts containing payload data. Channel quality indicators, such as CINR, can be derived from the preamble  302 , using techniques known in the art. As will be further understood by those of skill in the art, the AAS diversity map zone  308  is the location of the AAS downlink frame prefix (DLFP) which is decoded by the subscriber set during the scanning process. Channel parameters are contained in the uplink map  304  or the downlink map  306 . The AAS parameters and channel parameters are downlink subframe parameters that are used to optimize beamforming and other transmission parameters for the transmission of data from the base station  202  to the various subscriber sets. As discussed hereinabove, in current systems a subscriber set decodes both channel parameters and AAS parameters, thereby consuming large amounts of data processing resources. Embodiments of the invention use the channel quality indicator information derived from the preamble  302  to simplify the process of decoding downlink subframe parameters, as discussed in greater detail below. 
       FIG. 4  depicts a wireless communication system  400  in accordance with embodiments of the invention. As will be understood by those of skill in the art, the functional components shown in  FIG. 4  can be implemented in hardware, software or a combination thereof. Input signals are transmitted from a transmitter  402  (e.g., a base station) to one or more receivers  406 . 1 - 406 . m  (e.g., subscriber stations). The transmitter  402  includes a single antenna or an array of antennas  426  for communicating with the receivers  406 . 1 - m . The receivers  406 . 1 - m , may comprise a single antenna or an array of antennas  409 . i  for communicating with the transmitter  402 . In operation, a data signal s i  presented at the transmitter  402  for transmission to the receiver  406 . i  is transformed by the signal processor  421 . i  into a transmission signal represented by the vector x i . The signal processor  421 . i  performs the transformation using parameters provided by a scheduling and beamforming vector design module  425  and AMC selection module  428 . Channel parameters and AAS parameters are generated and provided to the signal processor  421 . i  by using processing logic in MAC  428  to initiate an 802.16 driver  430 . The processor  421 . i  is operable to embed the channel parameters and AAS parameters in downlink subframes that are transmitted from the transmit antennas  426  to propagate through a matrix channel H i  and are received by the receive antennas  409 . i  where they are represented by the vector y i . For a channel from the transmitter  402  to the i th  receiver  406 . i , the channel is denoted by H i , iε {1, 2, . . . , m}. The channel matrix H i  may be represented as an k i ×N matrix of complex entries representing the complex coefficients of the transmission channel between each transmit-receive antenna pair, where N represents the number of antennas of the transmitter  402  and k i  represents the number of antennas of the i th  receiver  406 . i . At the receiver  406 . i , the signal processing unit  405 . i  processes the y i  signals received on the k antennas to obtain a data signal, z i , which is an estimate of the transmitted data s i . The processing of the received y i  signals may include combining the y i  signals with appropriate combining vector information retrieved from the codebook  407 . i.    
     The channel matrix H i —which specifies the transmission channel between a transmitter and an i th  receiver—is estimated in the channel estimation signal processing unit  405 . i . For example, in a MIMO implementation, each receiver  406 . 1 - m  determines its MIMO channel matrix H i  by using pilot estimation or sounding techniques to determine or estimate the coefficients of the channel matrix Each receiver  406 . i  uses the estimated MIMO channel matrix or other channel-related information (which can be channel coefficients or channel statistics or their functions, such as a precoder, a beamforming vector or a modulation order) to generate CQI information that is to be used to configure/adapt the signals transmitted by the transmitter. In various embodiments of the invention, the CQI information includes, but is not limited to CINR and/or signal-to-noise ratio (SNR) information. 
     The CQI estimator  403 . i  generates a quantization/codebook index by accessing the receiver codebook  407 . i  which stores an indexed set of possible transmission profiles and/or channel matrices H i  along with associated CQI information so that the estimated channel matrix information  404 . i  generated by the signal processing unit  405 . i  can be used by the CQI estimator  403 . i  to retrieve a codebook index from the codebook  407 . i . The output of the CQI estimator  403 . i  is provided to a channel parameter detector  412   i  and to an AAS parameter detector  414   i . As will be discussed in greater detail herein below, embodiments of the present invention reduce the amount of processing required from the signal processing/channel estimator processor  405   i  by decoding only channel parameters when the subscriber set is in a non-AAS cell and decoding only AAS parameters when the subscriber set is in an AAS cell. The output of the AAS parameter detector  414 . i  and/or the channel parameter detector  418  is provided to an upper level processing stack for further processing by an application processor  418 . i    
     In various embodiments of the invention, the CQI information is used to simplify the decoding process. In the following discussion, CINR information will be used and an example. The CINR level can be used as an indicator of the location of the subscriber unit. As will be understood by those of skill in the art, the CINR is generally higher in an AAS cell. Therefore, if the CINR is above a predetermined level, the subscriber set is located in an AAS cell and the subscriber set will first decode AAS parameters, on the assumption that the subscriber set is in an AAS cell. If, on the other hand, the CINR is below the predetermined level, the subscriber set will decode channel parameter information first, on the assumption that the subscriber set is located in a non-AAS cell. 
       FIG. 5  is an illustration of the processing steps for implementing the various embodiments of the present invention. Processing begins in step  500 , where the signal is detected, and proceeds to step  502 , where the signal strength is measured by the subscriber station. In step  504 , all scannable frequencies are searched for channel parameters. In step  506 , a test is conducted to determine whether any channel parameters were detected in step  504 . If channel parameters were detected, processing proceeds to step  510 . If, however, no channel parameters were detected, processing proceeds to step  508  wherein the subscriber set scans all frequencies for AAS parameters. 
     If the result of the test conducted in step  502  indicates that CINR is high, processing proceeds to step  512  wherein the subscriber set searches all scannable frequencies for AAS parameters. In step  514 , a test is conducted to determine whether AAS parameters were detected. If the result of the test conducted in step  514  indicates that AAS parameters were detected, processing proceeds to step  510 . If, however, the result of the test conducted in step  514  indicates that no AAS parameters were detected, processing proceeds to step  516  wherein the subscriber set searches all scannable frequencies for channel parameters. Returning to step  502 , if the signal strength measurement indicates that CINR is undetermined, processing proceeds to step  518  wherein the subscriber set searches all scannable frequencies for channel parameters and AAS parameters. 
     As will be appreciated by those of skill in the art, existing prior solutions require (t s +t r )n operations, where: 
     t s =search time 
     t r =ranging time 
     n=number of frequencies 
     t r &gt;&gt;t s . 
     By contrast, embodiments of the present invention provide a flexible algorithm that requires either t s n or t r n operations. Therefore, the present invention provides a savings of t s n or t r n over existing techniques. 
     By now it will be appreciated that embodiments of the present invention provide a novel system and method for processing signals in a communication system. In one aspect, the method comprises: receiving a downlink subframe comprising a preamble, first and second sets of downlink subframe parameters, and a plurality of data bursts within a predetermined frequency band; processing data in the preamble to obtain channel quality indicator (CQI) information; and using the CQI information to select either the first set or the second set of downlink subframe parameters to process the data bursts in the downlink subframe. In some embodiments of this method, the CQI information comprises carrier-to-signal-plus-noise ratio (CINR) information. In other embodiments, the CQI information comprises signal-to-noise (SNR) information. In some embodiments of the invention, the first set of downlink subframe parameters comprises channel parameters and the second set of downlink subframe parameters comprises adaptive antenna system (AAS) parameters. In other embodiments of the invention, the method comprises initially searching all scannable frequencies within a predetermined frequency band for channel parameters if the CQI information is below a predetermined level. In that embodiment, the method further comprises subsequently searching all scannable frequencies in the frequency band for AAS parameters if no channel parameters are detected in the initial search. In another embodiment, the method further comprises initially searching all scannable frequencies within the frequency band for AAS parameters if the CQI information is above a predetermined level. That embodiment further comprises subsequently searching all scannable frequencies in the frequency band for the channel parameters if no channel parameters are detected in the initial search. 
     In another aspect, embodiments of the invention provide a method for processing data in a communication system, comprising: generating a downlink subframe comprising a preamble and a plurality of data bursts within a predetermined frequency band; embedding first and second sets of downlink subframe parameters in the downlink subframe; transmitting the downlink subframe; receiving the downlink subframe; processing data in the preamble to obtain channel quality indicator (CQI) information; and using the CQI information to select either the first set or set second set of downlink subframe parameters to process the data bursts in the downlink subframe. In some embodiments of this system, the CQI information comprises carrier-to-signal-plus-noise ratio (CINR) information. In other embodiments, the CQI information comprises signal-to-noise (SNR) information. In some embodiments of the invention, the first set of downlink subframe parameters comprises channel parameters and the second set of downlink subframe parameters comprises adaptive antenna system (AAS) parameters. In other embodiments of the invention, the method comprises initially searching all scannable frequencies within a predetermined frequency band for channel parameters if the CQI information is below a predetermined level. In that embodiment, the method further comprises subsequently searching all scannable frequencies in the frequency band for AAS parameters if no channel parameters are detected in the initial search. In another embodiment, the method further comprises initially searching all scannable frequencies within the frequency band for AAS parameters if the CQI information is above a predetermined level. That embodiment further comprises subsequently searching all scannable frequencies in the frequency band for the channel parameters if no channel parameters are detected in the initial search. 
     In yet another aspect, the invention provides a receiver for use in a wireless communication system, comprising: signal processing logic operable to receive a downlink subframe, wherein the subframe comprises a preamble, first and second sets of downlink subframe parameters, and a plurality of data bursts within a predetermined frequency band; processing logic operable to process data in the preamble to obtain channel quality indicator (CQI) information; and processing logic operable to use the CQI information to select either the first set or set second set of downlink subframe parameters to process the data bursts in the downlink subframe. In various embodiments of the invention, the CQI information comprises carrier-to-signal-plus-noise ratio (CINR) information. In other embodiments of the invention, the CQI information comprises signal-to-noise (SNR) information. In some embodiments of the invention, the first set of downlink subframe parameters comprises channel parameters and the second set of downlink subframe parameters comprises adaptive antenna system (AAS) parameters. In that embodiment, the receiver further comprises logic for initially searching all scannable frequencies within the frequency band for the channel parameters if the CQI information is below a predetermined level. In that embodiment, the receiver subsequently searches all scannable frequencies in the frequency band for AAS parameters if no channel parameters are detected in the initial search. In another embodiment, the receiver for initially searches all scannable frequencies within the frequency band for the AAS parameters if the CQI information is above a predetermined level. In that embodiment, the receiver subsequently searches all scannable frequencies in the frequency band for channel parameters if no AAS parameters are detected in the initial search. 
     The methods and systems for the communication system described herein may be implemented in hardware or in software stored on a computer-readable medium and executed as a computer program on a general purpose or special purpose computer to perform certain tasks. For a hardware implementation, the elements used to perform various signal processing steps at the transmitter and/or at the receiver may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof. In addition or in the alternative, a software implementation may be used, whereby some or all of the signal processing steps at each of the transmitter and receiver may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. It will be appreciated that the separation of functionality into modules is for illustrative purposes, and alternative embodiments may merge the functionality of multiple software modules into a single module or may impose an alternate decomposition of functionality of modules. In any software implementation, the software code may be executed by a processor or controller, with the code and any underlying or processed data being stored in any machine-readable or computer-readable storage medium, such as an on-board or external memory unit. 
     Although the described exemplary embodiments disclosed herein are directed to various communications systems and methods for using same, the present invention is not necessarily limited to the example embodiments illustrate herein. For example, various embodiments of a communication system disclosed herein may be implemented in connection with various proprietary or wireless communication standards. Thus, the particular embodiments disclosed above are illustrative only and should not be taken as limitations upon the present invention, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Accordingly, the foregoing description is not intended to limit the invention to the particular form set forth, but on the contrary, is intended to cover such alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims so that those skilled in the art should understand that they can make various changes, substitutions and alterations without departing from the spirit and scope of the invention in its broadest form. 
     Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element of any or all the claims. As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Metadata:
Filing Date: 20110801
Publication Date: 20150714
Grant Date: 20150714
Priority Date: 20070730
Inventors: LEVIN BRIAN D.
FLYNN CINDA L.
KEATING JEFFREY
MA STEPHEN C.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04L5/0053", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B17/309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B17/336", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L5/0053", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04B17/309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B17/336", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B17/336", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/0053", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 40338025