Patent Publication Number: US-2022239458-A1

Title: Repeater methods and apparatus

Description:
RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 16/695,150 which was filed on Nov. 25, 2019, which was published as U.S. patent publication US 2020-0412519 A1 on Dec. 31, 2020, and which claims the benefit of U.S. Provisional Patent application Ser. No. 62/868,999 which was filed on Jun. 30, 2019 each of which are hereby incorporated by reference in their entirety. 
    
    
     FIELD 
     The present invention relates to wireless communications methods and apparatus, and more particularly to repeater methods and apparatus. 
     BACKGROUND 
     Fifth generation cellular wireless technologies (or 5G, for short) will rely heavily on the use of millimeter wave spectrum bands 1 . As is well known, these bands suffer from poorer propagation than the ‘traditional’ cellular bands which are typically below 3 GHz (or 10 cm in wavelength). Furthermore, depending on the band, they could suffer from additional losses due to absorption from the atmosphere (e.g. due to water vapor, oxygen etc.). Human bodies, being mostly comprised of water, shadow the millimeter wave signal drastically. Also, diffraction (a mode of propagation where the signal bends on an edge that it encounters) results in a much greater loss as the wavelengths get shorter. Taken together, this implies that in millimeter wave bands, the cell radii will be on the order of 100-200 meters and furthermore will require line-of-sight (LOS) or strong specular reflections to sustain links. 
     The core technology used to address these propagation limitations is beamforming, wherein many antenna elements are used at the base station (called gNB in the 5G context) and the user equipment (UE), to allow constructive addition of their signals in space, in the direction of interest. The net effect is the amplitude sum of the signals from each antenna in the direction of interest and thereby a concentration of the electromagnetic radiation, i.e. a beam. If the user moves or something in the environment changes, a ‘new’ beam has to be found between the transmitter and the receiver. This is shown in  FIG. 1 . Thus, beamforming would generally have to be done on a per UE basis with associated measurement and control mechanisms to change the beam as needed. 
     Despite having such dynamic beamforming mechanisms, in some situations it will be virtually impossible to get coverage. Consider for example if a user is walking down a Manhattan street/avenue environment, if a user takes a turn from a street to an avenue, he/she could go from an excellent, line-of-sight (LOS) link to having no link at all. One could certainly densify the network by adding more and more gNBs to overcome these problems but that entails a substantial cost and network management penalty for operators. 
     Repeaters and/or relays are used to sometimes enhance the coverage area of a transmitting device. The term ‘repeaters’ is generally used when the ‘box’ doesn&#39;t attempt to decode the signal, but simply receives an RF signal over the air, amplifies it and re-transmits it. The term ‘relays’ is generally used when the box receives the RF signal, typically down converts from RF to baseband to do some digital processing up to and including a full decode of the bits, followed by re-encoding of the bits and up conversion back to RF prior to transmission. While the above is a general use of terminology in the art, the partition between what is a repeater and what is a relay is not strict. Repeaters can also be fully in-band wherein the receive frequency and the transmit frequency are the same (often called f1/f1 repeaters) or they can be out-of-band (often called f1/f2 repeaters), wherein the receive frequency and transmit frequency are different. 
     Relays suffer from having to fully decode the bits of a received signal before retransmitting. This suffers not only from the problem of cost as the decoding circuitry can add cost to a device but also from the delay associated with decoding and then re-encoding data prior to transmission. In highly dynamic environments such delays can be undesirable. 
     Repeaters and relays are not a new concept but in the case of beam forming systems where devices are subject to power transmission constraints face several implementation problems relating to the need for taking into consideration the timing of transmissions and/or beams being used by the source of a signal to be retransmitted, the transmission power constraints imposed upon a repeater, and the potential interference that can be caused by retransmission and/or the delays associated with retransmission of a signal. Furthermore, in the case of a repeater that is to support communications in multiple directions, e.g., uplink and downlink, there feedback from a signal being relayed in one direction may leak and be fully or partially retransmitted in the other direction. 
     For a variety of reasons, it is desirable to be able to implement a device which could rely transmissions in a dynamic environment where switching between uplink and downlink transmission occur without the need to fully decode traffic data being retransmitted, e.g., relayed. It would be desirable if the device operating as a relay need not appear and be recognized by the original transmitting device, e.g., base station or user equipment device, as a separate entity from the device to which the signal or signals is being relayed. In addition it would be desirable if, in at least some but not necessarily all embodiments, beam forming could be supported by a relay device on at least one, but possibly both, side of a relay device, e.g., a side facing client devices or a side facing a base station or access point. 
     SUMMARY 
     Various features relate to methods and apparatus for implementing repeater devices. In some embodiments the repeater devices can decode control and/or signaling information but normally does not re-encode data prior to retransmission. In various embodiments timing and/or other control information is based on received signals. The timing and control information is derived from received signals without the need to decode traffic data, e.g., text, voice or other data being communicated between a base station, sometimes referred to as an access point, and a user equipment (UE) device with in some cases the repeater of the invention located between the base station and UE device and the UE device sometimes simply being referred to as a UE. 
     Timing and/or frequency related control information maybe and sometimes is examined, e.g., decoded, and used to facilitate control of repeater operation, e.g., switching between a repeater downlink mode of operation in which signals from a base station are communicated to one or more UE devices, and a repeater uplink mode of operation in which signals are communicated to an access point from one or more UE devices. This may and in some but not necessarily all embodiments does include receiving and decoding SIB (system information broadcast) or SFI (slot format indication) broadcast to recover TDD timing information. Such decoding allows for the use of a relatively simple decoder that is capable of decoding broadcast control but without decoding traffic data being transmitted as part of the repeater operation. In other embodiments an uplink and/or downlink schedule is received by the repeater from a base station or other device via a communications channel, sometimes referred to as a side channel. The side channel maybe and sometimes is a wireless communications channel which is not used for communicating data to a UE. 
     Based on received signals, e.g., broadcast information, the repeater is able to determine when should operate in an uplink or downlink mode of operation. Switching of one or more transmit/receive switches is based on the when the repeater device is determined to switch between uplink and downlink modes of operation. 
     During individual modes of operation switch positions, gains, phases of signals being combined and/or power to amplifiers in the uplink or downlink signal paths are controlled to reduce or minimize interference from the signal path that is not to be used during the particular uplink or downlink mode of operation. 
     In some embodiments lookup tables containing sets of control information are accessed and used to control the components in the repeater depending on the mode of operation and/or the antenna configuration to be used at a given time. While gain of various applying components, phase of signals being combined and/or power to a particular device may and sometimes are all controlled in other embodiments one or two of these are controlled based on the mode of operation being implemented at a given time. For example, in some embodiments power to an amplifier is maintained regardless of the mode of operation to avoid transients due to power changes with phase of signals and/or gain of an amplifier being controlled to minimize interference between the uplink and downlink signal paths. In other embodiments simply phase of signals is controlled to reduce or minimize interference between the uplink and downlink signal paths. 
     While information which can be used to determine uplink/downlink scheduling is decoded and used in some embodiments to control whether a device operates in uplink or downlink modes of operation in other embodiments power of received signals is used to infer whether devices are operating in uplink or downlink mode of operation and the schedule of such modes of operation. Thus, while broadcast control/scheduling is decoded and used in some embodiments other embodiments do not need or rely on the decoding of broadcast or scheduling information. 
     While control/scheduling is decoded in some embodiments, such information is usually sent out prior to data transmissions. Thus, while a decoder is used to decode control/scheduling information in some embodiments the decoder need not and does not decode data transmission to particular devices and furthermore there is no need for an encoder to re-encode decoded data since, in at least some embodiments, the repeater does not re-encode decoded data for transmission to other devices. Thus, in some, but not necessarily all embodiments, the repeater of the invention lacks, i.e., does not include, an encoder or re-encoder. 
     The methods and apparatus can be used with devices which support the use of different antenna patterns at different times and is well suited for outdoor applications where the repeater maybe and sometimes is mounted on a pole such as a telephone pole or traffic light poll at an intersection. Through the use of repeaters, transmission range can be extended around building and corners of intersections in a cost effective and easy to implement manner that is relatively transparent to the user devices and access points in the system. 
     Because of the small delay associated with the retransmission of signals by a repeater implemented in accordance with the invention, signals received by UE devices and/or access points can be combined with the signals received directly from the original transmitting device and decoded, e.g., as if they were the result of a multipath transmission from the original transmitting device. 
     Some features are directed to a method of operating a repeater comprising detecting a time division duplex (TDD) timing schedule including a plurality of times at which a switch is made between uplink and downlink communication; and controlling a donor side switch (T/R switch) to change between a transmit position and a receive position based on the TDD timing schedule. In various embodiments the detecting of the uplink/downlink schedule is performed without re-encoding of data or signals being communicated, e.g. repeated or relayed. 
     Other features are related to a repeater including a process configured to control the repeater to detect a time division duplex (TDD) timing schedule including a plurality of times at which a switch is made between uplink and downlink communication; and controlling a donor side switch (T/R switch) to change between a transmit position and a receive position based on the TDD timing schedule. 
     While various features and methods have been described, all embodiments need not include all features or steps mentioned in the summary. Numerous additional features and embodiments are discussed in the detailed description which follows. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a drawing of an exemplary communications system in accordance with an exemplary embodiment. 
         FIG. 2  is a drawing of an exemplary circuit design implementation of an antenna array assembly which may be included in a repeater in accordance with an exemplary embodiment. 
         FIG. 3  is a drawing of another exemplary circuit design implementation of an antenna array assembly which may be included in a repeater in accordance with an exemplary embodiment. 
         FIG. 4  is a drawing of an exemplary first codebook, e.g., for an embodiment corresponding to the circuit design of the antenna array assembly shown in  FIG. 2 . 
         FIG. 5  is a drawing of an exemplary second codebook, e.g., an embodiment corresponding to the circuit design if the antenna array assembly shown in  FIG. 3 . 
         FIG. 6  is a drawing of an exemplary repeater in accordance with an exemplary embodiment. 
         FIG. 7A  is a first part of a flowchart of an exemplary method of operating a repeater, e.g., the repeater of  FIG. 6 , in accordance with an exemplary embodiment. 
         FIG. 7B  is a second part of a flowchart of an exemplary method of operating a repeater, e.g., the repeater of  FIG. 6 , in accordance with an exemplary embodiment. 
         FIG. 7 , comprises the combination of  FIG. 7A  and  FIG. 7B . 
         FIG. 8  is a drawing of an exemplary repeater in accordance with an exemplary embodiment. 
         FIG. 9A  is a first part of an exemplary assembly of components, which may be included in a repeater in accordance with an exemplary embodiment. 
         FIG. 9B  is a second part of an exemplary assembly of components, which may be included in a repeater in accordance with an exemplary embodiment. 
         FIG. 9  comprises the combination of  FIG. 9A  and  FIG. 9B . 
         FIG. 10  shows timing diagrams for autonomous TDD switch detection at a repeater with elements of the system being shown on the left, timing diagram corresponding to the element being shown on the right and the timing scale being consistent between the different elements as time progresses from the left side to the right side of the timing diagrams which are aligned to help understanding of the timing relationship between the operation of the different components. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a drawing of an exemplary communications system  100  in accordance with an exemplary embodiment. Exemplary communications system  100  includes a base station  1  (BS  1 )  102 , base station  2   104 , repeater  1   106 , network node  108 , and network node  110  coupled together as shown in  FIG. 1 . Base station  1   102  has a corresponding wireless coverage area  103 . Base station  2   104  has a corresponding wireless coverage area  105 . Repeater  1   106  has a corresponding service side wireless coverage area  107 . The exemplary communications system  100  further includes a plurality of user equipment (UE) devices. At least some of the UEs are mobile devices which may move throughout the system  100 . As shown in  FIG. 1 , a plurality of UEs (UE  1 A  112 , UE  2 A  114 , . . . , UE N 1   116 ) are currently located within wireless coverage area  103  and may, and sometimes do: i) receive downlink wireless signals from BS  1   102  and ii) transmit uplink wireless signals to BS  1   102 . As shown in  FIG. 1 , a plurality of UEs (UE  1 B  118 , . . . , UE mB  120 ) are currently located within wireless coverage area  105  and may, and sometimes do: i) receive downlink wireless signals from BS  2   104  and ii) transmit uplink wireless signals to BS  2   104 . As shown in  FIG. 1 , a plurality of UEs (UE  1 C  122 , UE  2 C  124 , . . . , UE NC  126 ) are currently located within the repeater  1  service side wireless coverage area  107  and may, and sometimes do: i) receive downlink wireless signals from repeater  1   106  and ii) transmit uplink wireless signals to repeater  1   106 . 
     Base station  1   102  is coupled to network node  108  via communications link  128 . Network node  108  is coupled to other network nodes, other base stations and/or the Internet via communications link  132 . Base station  2   104  is coupled to other network nodes, other base stations and/or the Internet via communications link  130 . Repeater  1   106  is coupled to network node  110  via communications link  134 . Network node  110  is coupled to other network nodes, other repeaters and/or the Internet via communications link  136 . 
     Repeater  1   106  includes a donor side including one or more donor antennas for communicating with base station  1   102 . Repeater  1   106  includes a service including one or more donor antennas for communicating with user equipment (UE) devices with the repeater  1  service side coverage area  107 . Repeater  1   106  acts as an intermediary device between base station  1   102  and UE devices, which are located within repeater  1  service side coverage area  107 . In some embodiments, repeater  1   106  is strategically located and used to provide coverage to an area which normally has no or poor reception with regard to wireless signals from base station  1 , e.g., due to obstacles in the path, e.g., a mountain, a building, etc. 
       FIG. 2  is a drawing of an exemplary circuit design implementation of an antenna array assembly  200  which may be included in a repeater in accordance with an exemplary embodiment. The exemplary circuit design implementation of  FIG. 2  uses switches and weights to null the self-interference for the case of separate Transmit (Tx) and Receive (Rx) arrays. The exemplary circuit design implementation of  FIG. 2  includes a donor receive antenna  1  (DRA 1 )  202 , donor receive antenna  2  (DRA 2 )  204 , low noise amplifier (LNA)  206 , LNA  208 , signal mixer  210 , signal mixer  212 , combiner  214 , splitter  216 , signal mixer  218 , signal mixer  220 , power amplifier (PA)  222 , PA  224 , downlink (DL) Transmit/Receive (T/R) switch  226 , DL T/R switch  228 , service transmit antenna  1  (STA 1 )  230  and service transmit antenna  2  (STA  2 )  232 . 
     The output of DRA  1   202  is coupled to the input of LNA  206 . LNA  206  is controlled via a control gain signal received on donor receive gain  1 (DRG 1 ) control line  207 . The output of LNA  206  is input to mixer  210 , which is mixed with a control weight signal received on donor received weight  1 (DRW 1 ) control line  211 . The output of the mixer  210  is a first input to signal combiner  214 . 
     The output of DRA  2   204  is coupled to the input of LNA  208 . LNA  208  is controlled via a control gain signal received on donor receive gain  2 (DRG 2 ) control line  209 . The output of LNA  208  is input to mixer  212 , which is mixed with a control weight signal received on donor received weight  2 (DRW 2 ) control line  213 . The output of the mixer  212  is a second input to signal combiner  214 . 
     The output of combiner  214  is coupled to the input of splitter  216 . A first output of splitter  216  is coupled to a first input of mixer  218 . A second input to mixer  218  is a control weight signal received on service transmit weight  1  (STW 1 ) control line  219 . The output of mixer  218  is coupled to the input of PA  222 . PA  222  is controlled via a control gain signal received on service transmit gain  1 (STG 1 ) control line  223 . The output of PA  222  is coupled to an input of T/R switch  226 , which is a DL switch. T/R switch  226  is controlled to be closed or open based on the signal received on DL switch control line  227 . The output of switch  226  is coupled to the input of service transmit antenna  1  (STA 1 )  230 . 
     A second output of splitter  216  is coupled to a first input of mixer  220 . A second input to mixer  220  is a control weight signal received on service transmit weight  2  (STW 2 ) control line  221 . The output of mixer  220  is coupled to the input of PA  224 . PA  224  is controlled via a control gain signal received on service transmit gain  2  (STG 2 ) control line  225 . The output of PA  225  is coupled to an input of T/R switch  228 , which is a DL switch. T/R switch  228  is controlled to be closed or open based on the signal received on DL switch control line  229 . The output of switch  228  is coupled to the input of service transmit antenna  2  (STA 2 )  232 . 
     The exemplary circuit design implementation of  FIG. 2  further includes a service receive antenna  1  (SRA 1 )  234 , service receive antenna  2  (SRA 2 )  236 , low noise amplifier (LNA)  238 , LNA  240 , signal mixer  242 , signal mixer  244 , combiner  246 , splitter  248 , signal mixer  250 , signal mixer  252 , power amplifier (PA)  254 , PA  256 , Uplink (UL) Transmit/Receive (T/R) switch  258 , UL T/R switch  260 , donor transmit antenna  1  (DTA 1 )  262  and donor transmit antenna  2  (DTA  2 )  264 . 
     The output of SRA  1   234  is coupled to the input of LNA  238 . LNA  238  is controlled via a control gain signal received on service receive gain  1 (SRG 1 ) control line  239 . The output of LNA  238  is input to mixer  242 , which is mixed with a control weight signal received on service receive weight  1 (SRW 1 ) control line  243 . The output of the mixer  242  is a first input to signal combiner  246 . 
     The output of SRA  2   236  is coupled to the input of LNA  240 . LNA  240  is controlled via a control gain signal received on service receive gain  2  (SRG 2 ) control line  241 . The output of LNA  240  is input to mixer  244 , which is mixed with a control weight signal received on service received weight  2  (SRW 2 ) control line  245 . The output of the mixer  244  is a second input to signal combiner  246 . 
     The output of combiner  246  is coupled to the input of splitter  248 . A first output of splitter  248  is coupled to a first input of mixer  250 . A second input to mixer  250  is a control weight signal received on donor transmit weight  1  (DTW 1 ) control line  251 . The output of mixer  240  is coupled to the input of PA  254 . PA  254  is controlled via a control gain signal received on donor transmit gain  1  (DTG 1 ) control line  255 . The output of PA  254  is coupled to an input of T/R switch  258 , which is a UL switch. T/R switch  258  is controlled to be closed or open based on the signal received on UL switch control line  259 . The output of switch  258  is coupled to the input of donor transmit antenna  1  (DTA 1 )  262 . 
     A second output of splitter  248  is coupled to a first input of mixer  252 . A second input to mixer  252  is a control weight signal received on donor transmit weight  2  (DTW 2 ) control line  253 . The output of mixer  252  is coupled to the input of PA  256 . PA  256  is controlled via a control gain signal received on donor transmit gain  2  (DTG 2 ) control line  257 . The output of PA  256  is coupled to an input of T/R switch  260 , which is a UL switch. T/R switch  260  is controlled to be closed or open based on the signal received on UL switch control line  261 . The output of switch  260  is coupled to the input of donor transmit antenna  2  (DTA 2 )  264 . 
       FIG. 3  is a drawing of an exemplary circuit design implementation of an antenna array assembly  300  which may be included in a repeater in accordance with an exemplary embodiment. The exemplary circuit design implementation of  FIG. 3  uses switches and weights to null the self-interference for the case of common Transmit (Tx) and Receive (Rx) arrays. The exemplary circuit design implementation of  FIG. 3  includes a donor antenna  1  (DA 1 )  302 , donor antenna  2  (DA 2 )  304 , donor T/R switch  1  (DTRS 1 )  306 , donor T/R switch  2  (DTRS 2 )  308 , low noise amplifier (LNA)  310 , LNA  312 , signal mixer  314 , signal mixer  316 , combiner  318 , splitter  320 , signal mixer  322 , signal mixer  324 , power amplifier (PA)  326 , PA  328 , Service Transmit/Receive (T/R) switch  1  (STRS 1 )  330 , STRS 2   332 , service antenna  1  (SA 1 )  334  and service antenna  2  (SA 2 )  336 . 
     DA 1   302  is coupled to DTRS 1   306 . The position of DTRS 1   306  is controlled based on the T/R receive control signal received on T/R control line  307 . When DA 1   302  is to be used as a receive antenna DTRS 1   306  is controlled to couple the DA 1   302  to the input of LNA  310 , thus routing a received signal from DA 1   302  to an input of LNA  310 . LNA  310  is controlled via a control gain signal received on donor receive gain  1  (DRG 1 ) control line  311 . The output of LNA  310  is input to mixer  314 , which is mixed with a control weight signal received on donor receive weight  1  (DRW 1 ) control line  315 . The output of the mixer  314  is a first input to signal combiner  318 . 
     DA 2   304  is coupled to DTRS 2   308 . The position of DTRS 2   308  is controlled based on the T/R receive control signal received on T/R control line  309 . When DA 2   304  is to be used as a receive antenna DTRS 2   308  is controlled to couple the DA 2   304  to the input of LNA  312 , thus routing a received signal from DA 2   304  to an input of LNA  312 . LNA  312  is controlled via a control gain signal received on donor receive gain  1  (DRG 2 ) control line  313 . The output of LNA  312  is input to mixer  316 , which is mixed with a control weight signal received on donor receive weight  2  (DRW 2 ) control line  317 . The output of the mixer  316  is a second input to signal combiner  318 . 
     The output of combiner  318  is coupled to the input of splitter  320 . A first output of splitter  320  is coupled to a first input of mixer  322 . A second input to mixer  322  is a control weight signal received on service transmit weight  1  (STW 1 ) control line  323 . The output of mixer  322  is coupled to the input of PA  326 . PA  326  is controlled via a control gain signal received on service transmit gain  1 (STG 1 ) control line  327 . The output of PA  326  is coupled to service T/R switch  1  (STRS 1 )  330 . The position of STRS 1   330  is controlled based on the T/R receive control signal received on T/R control line  331 . When SA 1   334  is to be used as a transmit antenna STRS 1   330  is controlled to couple the output of PA  326  to SA 1   334 , thus routing a generated transmit signal from PA  326  to SA 1   334 . 
     A second output of splitter  320  is coupled to a first input of mixer  324 . A second input to mixer  324  is a control weight signal received on service transmit weight  2  (STW 2 ) control line  325 . The output of mixer  324  is coupled to the input of PA  328 . PA  328  is controlled via a control gain signal received on service transmit gain  2  (STG 2 ) control line  329 . The output of PA  328  is coupled to service T/R switch  2  (STRS 2 )  332 . The position of STRS 2   332  is controlled based on the T/R receive control signal received on T/R control line  333 . When SA 2   336  is to be used as a transmit antenna STRS 2   332  is controlled to couple the output of PA  328  to SA 2   336 , thus routing a generated transmit signal from PA  328  to SA 2   336 . 
     The exemplary circuit design implementation of  FIG. 3  includes low noise amplifier (LNA)  338 , LNA  340 , signal mixer  342 , signal mixer  344 , combiner  346 , splitter  348 , signal mixer  350 , signal mixer  352 , and power amplifier (PA)  354 . 
     SA 1   3334  is coupled to STRS 1   330 . The position of STRS 1   330  is controlled based on the T/R receive control signal received on T/R control line  331 . When SA 1   302  is to be used as a receive antenna STRS 1   330  is controlled to couple the SA 1   334  to the input of LNA  3338 , thus routing a received signal from SA 1   334  to an input of LNA  3338 . LNA  338  is controlled via a control gain signal received on service receive gain  1  (SRG 1 ) control line  339 . The output of LNA  338  is input to mixer  342 , which is mixed with a control weight signal received on service receive weight  1  (SRW 1 ) control line  343 . The output of the mixer  342  is a first input to signal combiner  346 . 
     SA 2   336  is coupled to STRS 2   332 . The position of STRS 2   332  is controlled based on the T/R receive control signal received on T/R control line  333 . When SA 2   336  is to be used as a receive antenna STRS 2   332  is controlled to couple the SA 2   336  to the input of LNA  340 , thus routing a received signal from SA 2   336  to an input of LNA  340 . LNA  340  is controlled via a control gain signal received on service receive gain  2  (SRG 2 ) control line  341 . The output of LNA  340  is input to mixer  344 , which is mixed with a control weight signal received on service receive weight  2  (SRW 2 ) control line  345 . The output of the mixer  344  is a second input to signal combiner  346 . 
     The output of combiner  346  is coupled to the input of splitter  348 . A first output of splitter  348  is coupled to a first input of mixer  350 . A second input to mixer  350  is a control weight signal received on donor transmit weight  1  (DTW 1 ) control line  351 . The output of mixer  350  is coupled to the input of PA  354 . PA  354  is controlled via a control gain signal received on donor transmit gain  1  (DTG 1 ) control line  355 . The output of PA  354  is coupled to donor T/R switch  1  (DTRS 1 )  306 . The position of DTRS 1   306  is controlled based on the T/R receive control signal received on T/R control line  307 . When DA 1   302  is to be used as a transmit antenna DTRS 1   3306  is controlled to couple the output of PA  354  to DA 1   302 , thus routing a generated transmit signal from PA  354  to DA 1   302 . 
     A second output of splitter  348  is coupled to a first input of mixer  353 . A second input to mixer  352  is a control weight signal received on donor transmit weight  2  (DTW 2 ) control line  353 . The output of mixer  352  is coupled to the input of PA  356 . PA  356  is controlled via a control gain signal received on donor transmit gain  2  (DTG 2 ) control line  357 . The output of PA  356  is coupled to donor T/R switch  2  (DTRS 2 )  308 . The position of DTRS 2   308  is controlled based on the T/R receive control signal received on T/R control line  309 . When DA 2   304  is to be used as a transmit antenna DTRS 2   308  is controlled to couple the output of PA  356  to DA 2   304 , thus routing a generated transmit signal from PA  3356  to DA 2   304 . 
       FIG. 4  is a drawing of an exemplary codebook for an exemplary embodiment 1, e.g., an embodiment corresponding to the circuit design shown in  FIG. 2 . First column  402  includes antenna arrangement information. Second column  404  includes mode information. Third column  406  includes values for the donor receive weight  1  (DRW 1 ) control element corresponding to different antenna arrangements. Fourth column  408  includes values for the donor receive weight  2  (DRW 2 ) control element corresponding to different antenna arrangements. Fifth column  410  includes values for the service transmit weight  1  (STW 1 ) control element corresponding to different antenna arrangements. Sixth column  412  includes values for the service transmit weight  2  (STW 2 ) control element corresponding to different antenna arrangements. Seventh column  414  includes values for the donor receive gain  1  (DRG 1 ) control element corresponding to different antenna arrangements. Eighth column  416  includes values for the donor receive gain  2  (DRG 2 ) control element corresponding to different antenna arrangements. Ninth column  418  includes values for the service transmit gain  1  (STG 1 ) control element corresponding to different antenna arrangements. Tenth column  420  includes values for the service transmit gain  2  (STG 2 ) control element corresponding to different antenna arrangements. Eleventh column  422  includes values for the service receive weight  1  (SRW 1 ) control element corresponding to different antenna arrangements. Twelfth column  424  includes values for the service receive weight  2  (SRW 2 ) control element corresponding to different antenna arrangements. Thirteenth column  426  includes values for the donor transmit weight  1  (DTW 1 ) control element corresponding to different antenna arrangements. Fourteenth column  428  includes values for the donor transmit weight  2  (DTW 2 ) control element corresponding to different antenna arrangements. Fifteenth column  430  includes values for the service receive gain  1  (SRG 1 ) control element corresponding to different antenna arrangements. Sixteenth column  432  includes values for the service receive gain  2  (SRG 2 ) control element corresponding to different antenna arrangements. Seventeenth column  434  includes values for the donor transmit gain  1  (DTG 1 ) control element corresponding to different antenna arrangements. Eighteenth column  436  includes values for the donor transmit gain  2  (DTG 2 ) control element corresponding to different antenna arrangements. 
     First row  438  includes information identifying the codebook  400  as corresponding to exemplary embodiment 1. Second row  440  includes column header information: i) identifying that the first column  402  includes antenna arrangement (AA) information, ii) identifying the second column  404  includes mode information, and iii) identifying that third column  406  through eighteenth column  436  includes control element information. Third row  442  includes column header information identifying a particular control element for each of the third column  406  through eighteenth column  436 . 
     Fourth row  444  includes values for each of the control elements corresponding to antenna arrangement  1  (AA 1 ) and uplink mode. Fifth row  446  includes values for each of the control elements corresponding to antenna arrangement  1  (AA 1 ) and downlink mode. Sixth row  448  includes values for each of the control elements corresponding to antenna arrangement  2  (AA 2 ) and uplink mode. Seventh row  450  includes values for each of the control elements corresponding to antenna arrangement  2  (AA 2 ) and downlink mode. Eighth row  452  includes values for each of the control elements corresponding to antenna arrangement  3  (AA 3 ) and uplink mode. Ninth row  454  includes values for each of the control elements corresponding to antenna arrangement  3  (AA 3 ) and downlink mode. Tenth row  456  includes values for each of the control elements corresponding to antenna arrangement X (AAX) and uplink mode. Eleventh row  458  includes values for each of the control elements corresponding to antenna arrangement X (AAX) and downlink mode. 
       FIG. 5  is a drawing of an exemplary codebook for an exemplary embodiment 2, e.g., an embodiment corresponding to the circuit design shown in  FIG. 3 . First column  502  includes antenna arrangement information. Second column  504  includes mode information. Third column  506  includes values for the donor receive weight  1  (DRW 1 ) control element corresponding to different antenna arrangements. Fourth column  508  includes values for the donor receive weight  2  (DRW 2 ) control element corresponding to different antenna arrangements. Fifth column  510  includes values for the service transmit weight  1  (STW 1 ) control element corresponding to different antenna arrangements. Sixth column  512  includes values for the service transmit weight  2  (STW 2 ) control element corresponding to different antenna arrangements. Seventh column  514  includes values for the donor receive gain  1  (DRG 1 ) control element corresponding to different antenna arrangements. Eighth column  516  includes values for the donor receive gain  2  (DRG 2 ) control element corresponding to different antenna arrangements. Ninth column  518  includes values for the service transmit gain  1  (STG 1 ) control element corresponding to different antenna arrangements. Tenth column  520  includes values for the service transmit gain  2  (STG 2 ) control element corresponding to different antenna arrangements. Eleventh column  522  includes values for the service receive weight  1  (SRW 1 ) control element corresponding to different antenna arrangements. Twelfth column  524  includes values for the service receive weight  2  (SRW 2 ) control element corresponding to different antenna arrangements. Thirteenth column  526  includes values for the donor transmit weight  1  (DTW 1 ) control element corresponding to different antenna arrangements. Fourteenth column  528  includes values for the donor transmit weight  2  (DTW 2 ) control element corresponding to different antenna arrangements. Fifteenth column  530  includes values for the service receive gain  1  (SRG 1 ) control element corresponding to different antenna arrangements. Sixteenth column  532  includes values for the service receive gain  2  (SRG 2 ) control element corresponding to different antenna arrangements. Seventeenth column  534  includes values for the donor transmit gain  1  (DTG 1 ) control element corresponding to different antenna arrangements. Eighteenth column  536  includes values for the donor transmit gain  2  (DTG 2 ) control element corresponding to different antenna arrangements. 
     First row  538  includes information identifying the codebook  400  as corresponding to exemplary embodiment 1. Second row  540  includes column header information: i) identifying that the first column  502  includes antenna arrangement (AA) information, ii) identifying the second column  504  includes mode information, and iii) identifying that third column  506  through eighteenth column  536  includes control element information. Third row  542  includes column header information identifying a particular control element for each of the third column  506  through eighteenth column  536 . 
     Fourth row  544  includes values for each of the control elements corresponding to antenna arrangement  1  (AA 1 ) and uplink mode. Fifth row  546  includes values for each of the control elements corresponding to antenna arrangement  1  (AA 1 ) and downlink mode. Sixth row  548  includes values for each of the control elements corresponding to antenna arrangement  2  (AA 2 ) and uplink mode. Seventh row  550  includes values for each of the control elements corresponding to antenna arrangement  2  (AA 2 ) and downlink mode. Eighth row  552  includes values for each of the control elements corresponding to antenna arrangement  3  (AA 3 ) and uplink mode. Ninth row  554  includes values for each of the control elements corresponding to antenna arrangement  3  (AA 3 ) and downlink mode. Tenth row  556  includes values for each of the control elements corresponding to antenna arrangement X (AAX) and uplink mode. Eleventh row  558  includes values for each of the control elements corresponding to antenna arrangement X (AAX) and downlink mode. 
       FIG. 6  is a drawing of an exemplary repeater  600  in accordance with an exemplary embodiment. Exemplary repeater  600  includes antenna array assembly  602 , e.g., antenna array assembly  200  of  FIG. 2  or antenna array assembly  300  of  FIG. 3 , a processor  601  and a memory  611  which are coupled together by a bus formed by connections  610 ,  612 ,  620 ,  622 ,  614 ,  616  and  618  over which data and control signals can be transmitted. The processor  601  controls the repeater to operate in accordance with the invention, e.g., to implement any one of the methods shown in the other figures of the application which show steps or the methods implemented by a repeater. The processor  603  includes a time division duplex (TDD) schedule detector  603  and a TDD mode controller  606  which in some embodiments are implemented in hardware but in other embodiments are implemented by the processor running software which configures the processor to control the repeater in accordance with the invention. A codebook of weights and gains  604  is stored in memory  611  and can be accessed as needed by the processor  601  to retrieve and/or determine the sets of weights and gains to be used at a particular point in time based on a determined TDD schedule that can be detected by the detector  603  based on received information and/or signals. One or more TDD schedules maybe and sometimes are also stored in memory  611 . In some embodiments the memory  611  includes the assembly of components shown in  FIG. 9  which comprises the combination of  FIGS. 9A and 9B . The codebook of weights and gains  604 , is, e.g., one of codebook  400  of  FIG. 4  or codebook  500  of  FIG. 5 . 
     Donor side and service side received signals  608  are input to TDD schedule detector  602 , which processes the received signals, determines when a mode change should occur, and generates signals  610 , communicating information indicating when a mode change should occur, e.g., from uplink mode to downlink mode or from downlink mode to uplink mode, to the TDD code controller. In some embodiments, the TDD schedule detector  603  receives at least one of a system information broadcast (SIB) or a slot format information (SFI) broadcast and decodes the received signal to recover TDD timing information, e.g., a TDD timing schedule, and uses the recovered TDD timing schedule and current time with respect to the schedule to detect transitions, e.g., from uplink mode of operation to downlink mode of operation, or from downlink mode of operation to uplink mode of operation. In some other embodiments, the TDD schedule detector  603  monitors for and detects gaps in base station and UE transmissions, and uses the detected gap and information indicating whether the transmission preceding the gap were downlink or uplink, to detect the transition, e.g., from uplink to downlink mode of operation or from downlink to uplink mode of operation. 
     The TDD mode controller  606  uses the received TDD schedule detection information  610  and codebook information  612 , to determine, e.g., based on a codebook lookup, a set of weight values  620  and a set of gains values  622  which are input to the antenna array assembly  602 . In addition the TDD mode controller  606  generates T/R switch control signals  614 , UL switch control signal  616  and DL switch control signals, which are sent to the antenna array assembly. 
       FIG. 7 , comprising the combination of  FIG. 7A  and  FIG. 7B , is a flowchart  700  of an exemplary method of operating a repeater, e.g., repeater  600  of  FIG. 6 , in accordance with an exemplary embodiment. Operation of the exemplary method starts in step  702 , in which the repeater is powered on and initialized. Operation proceeds from step  702  to step  704 . 
     In step  706  the repeater detects a time division duplex (TDD) timing schedule including a plurality of time at which a switch is made between uplink and downlink communications. In some embodiments, step  706  includes steps  708  and  710 . In some other embodiments, step  706  includes step  712  and  714 . 
     In step  708  the repeater receives at least one of a system information broadcast (SIB) or a slot format information (SFI) broadcast. Operation proceeds from step  708  to step  710 . In step  710  the repeater decodes the received at least one of the SIB broadcast or SFI broadcast to recover TDD timing information. Operation proceeds from step  710  to step  716 . 
     In step  716  the repeater monitors current time and detects a transition in accordance with the timing schedule. Step  716  includes steps  718  and  720 , one of which is performed for each detected transition. Step  716  is performed repetitively, e.g., on an ongoing basis. In step  718  the repeater detects a transition from an uplink mode of operation to a downlink mode of operation in accordance with the recovered TDD timing information. Operation proceeds from step  718 , via connecting node B  730  to step  738 . Returning to step  720 , in step  720  the repeater detects a transition from a downlink mode of operation to an uplink mode of operation in accordance with the recovered TDD timing information. Operation proceeds from step  720 , via connecting node A  728  to step  732 . 
     Returning to step  712 , in step  712  the repeater monitors for at least one gap in base station (BS) and user equipment (UE) transmissions. Step  712  is performed repetitively, e.g., on an ongoing basis. Operation proceeds from step  712  to step  714 , in response to a detected gap. In step  714  the repeater determines if uplink or downlink signals preceded the gap. Operation proceeds from step  714  to step  722 . In step  722 , if the repeater has determined that the uplink transmission preceded the gap, then operation proceeds from step  722  to step  724 , in which the repeater detects a transition from an uplink mode of operation to a downlink mode of operation. Operation proceeds from step  724 , via connecting node B  730  to step  738 . 
     Returning to step  722 , if the repeater has determined that the downlink transmission preceded the gap, then operation proceeds from step  722  to step  726 , in which the repeater detects a transition from a downlink mode of operation to an uplink mode of operation. Operation proceeds from step  726 , via connecting node A  728  to step  732 . 
     Returning to step  732 , in step  732  the repeater sets a first set of donor side antenna receiver weights to a first set of values which causes constructive cancellation when combining signal received from donor side receive antenna outputs of a donor side antenna. Operation proceeds from step  732  to step  734 . In step  734  the repeater decrease the gain of a donor side receiver amplifier by decreasing a voltage supplied to the donor side receiver amplifier to by decreasing a bias current supplied to the donor side receiver amplifier. In some embodiments, step  734  includes step  736  in which the repeater reduces the voltage supplied to the amplifier to a lower voltage than a voltage which is supplied during the downlink mode of operation. Operation proceeds from step  734  to step  744 . 
     Returning to step  738 , in step  738  the repeater sets the first set of donor side antenna receiver weights to a second set of values used in said downlink mode of operation, said second set of values differing from said first set of values in terms of phase components but not in terms of amplitude components. In some embodiments in step  738  the repeater automatically controls which of a plurality of antenna weights is used at a given time, and in some cases automatically selects, based on a received or selected set of control information which of a plurality of donor side antenna weights are used at a given time, e.g., based on the TDD timing schedule. 
     Operation proceeds from step  738  to step  740 . In step  740  the repeater increases the gain of a donor side receiver amplifier by increasing a voltage supplied to the donor side receiver amplifier to by increasing a bias current supplied to the donor side receiver amplifier. In some embodiments, step  740  includes step  742  in which the repeater increases the voltage supplied to the amplifier to a higher voltage than a voltage which is supplied during the uplink mode of operation. Operation proceeds from step  740  to step  744 . 
     In step  744  the repeater controls a donor side switch to change between a transmit and receive position based on the TDD timing schedule. Operation proceeds from step  744  to step  746 . 
     In step  746  the repeater receives a signal and re-transmits said signal in accordance with a set of control information including switch setting, antenna weights and antennas gains. In some embodiments, step  746  includes step  748 , in which the repeater receives said signal and re-transmits said signal in accordance with the set of control information including switch setting, antenna weights and antennas gains without performing decoding/encoding operations and/or decrypting/encrypting operations. In some embodiments, step  748  includes step  750  in which the repeater uses a beam which is narrower for donor side communications than for service side communications. 
       FIG. 8  is a drawing of an exemplary repeater  800  in accordance with an exemplary embodiment. Exemplary repeater  800  is, e.g., repeater  106  of system  100  of  FIG. 1 , repeater  600  of  FIG. 6 , and/or a repeater implementing the method of flowchart  700  of  FIG. 7 . 
     Repeater  800  includes a processor  802 , e.g., a CPU, an antenna array assembly  804 , a network interface  806 , e.g., a wired or optical interface, an assembly of hardware components  808 , e.g., an assembly of circuits, an memory  810  coupled together via a bus  811  over which the various elements many interchange data and information. Network interface  806  includes a receiver  844  and a transmitter  846 . Network interface  806  couples the repeater  800  to network nodes, e.g., network node  110 , and/or to macro cell base stations, e.g., via a backhaul network. In many cases a network interface is not needed and not included in the repeater. In at least some applications the point of putting in a repeater is to avoid the need for extending a backhaul and the corresponding associated cost. In such applications a repeater without a network interface for a wired backhaul connection can be cost effective. In some such cases control and/or configuration of the repeater can be and is supported by using a wireless channel and the repeaters wireless interface for device configuration and management. In some such cases the wireless channel used for repeater device configuration is referred to as a side channel since it is different from, and often separate from, the wireless channel or channels used to communicate control information and data to UE devices. Thus in at least some embodiments the repeater does not have a wired or optical network interface with control and configuration being via one of the wireless interfaces included in the repeater. Accordingly, while a wired network interface is shown in various figures it is an optional element and is not included in at least some embodiments and in such embodiments the network interface maybe implemented as a wireless network interface. 
     Antenna array assembly  804  includes antenna array assembly circuitry  812 , donor side antennas  814  and service side antennas  816  coupled together. Donor side antennas  814  includes donor side antennas or donor side antenna elements ( 818 ,  802 ). In some embodiments, donor side antennas  814  further includes donor side antennas or donor side antenna elements ( 822 ,  824 ). Service side antennas  816  includes service side antennas or service side antenna elements ( 826 ,  828 ). In some embodiments, service side antennas  816  further includes service side antennas or service side antenna elements ( 830 ,  832 ). In some embodiments, antenna array assembly  804  is antenna array assembly  200  of  FIG. 2 ; donor side antennas ( 818 ,  820 ,  822 ,  824 ) of antenna array  804  are donor side antennas ( 202 ,  204 ,  262 ,  264 ) of antenna array  200  of  FIG. 2 ; and service side antennas ( 826 ,  828 ,  830 ,  832 ) of antenna array  804  are service side antennas ( 230 ,  232 ,  234 ,  236 ) of antenna array  200  of  FIG. 2 . In some embodiments, antenna array assembly  804  is antenna array assembly  300  of  FIG. 3 ; donor side antennas ( 818 ,  820 ) of antenna array  804  are donor side antennas ( 302 ,  304 ) of antenna array  300  of  FIG. 3 ; and service side antennas ( 826 ,  828 ) of antenna array  804  are service side antennas ( 334 ,  336 ) of antenna array  300  of  FIG. 3 . In some embodiments, antenna array assembly  804  is antenna array assembly  602  of  FIG. 6 . Repeater  800  communicates with a base station, e.g., base station  1   102 , via wireless signals communicated via donor side antennas  814 . Repeater  800  communicates with a UE, e.g., UE  1 C  122 , via wireless signals communicated via service side antennas  816 . 
     Memory  810  includes a control routine  834  an assembly of components  838 , e.g., an assembly of software components, and data/information  840 . Data information  840  includes a codebook  842 . Codebook  842  is, e.g., codebook  400  or  FIG. 4  or codebook  500  of  FIG. 5 . 
       FIG. 9 , comprising the combination of  FIG. 9A  and  FIG. 9B , is a drawing of an assembly of components  900 , comprising the combination of Part A  901  and Part B  903 , in accordance with an exemplary embodiment. The assembly of components  900  can be and sometime is included in the exemplary repeater  106  of  FIG. 1 , exemplary repeater  800  of  FIG. 8 , exemplary repeater  600  of  FIG. 6 , a repeater implementing the method flowchart  700  of  FIG. 7 , and/or a repeater shown and/or described with respect to any of the other figures. 
     The components in the assembly of components  900  can, and in some embodiments are, implemented fully in hardware within the processor  802 , e.g., as individual circuits. The components in the assembly of components  900  can, and in some embodiments are, implemented fully in hardware within the assembly of components  808 , e.g., as individual circuits corresponding to the different components. In other embodiments some of the components are implemented, e.g., as circuits, within the processor  802  with other components being implemented, e.g., as circuits within assembly of components  808 , external to and coupled to the processor  802 . As should be appreciated the level of integration of components on the processor and/or with some components being external to the processor may be one of design choice. Alternatively, rather than being implemented as circuits, all or some of the components may be implemented in software and stored in the memory  810  of the repeater  800 , with the components controlling operation of the repeater to implement the functions corresponding to the components when the components are executed by a processor, e.g., processor  802 . In some such embodiments, the assembly of components  900  is included in the memory  810  as assembly of components  838 . In still other embodiments, various components in assembly of components  900  are implemented as a combination of hardware and software, e.g., with another circuit external to the processor  802  providing input to the processor  802  which then under software control operates to perform a portion of a component&#39;s function. While processor  802  is shown in the  FIG. 8  embodiment as a single processor, e.g., computer, it should be appreciated that the processor  802  may be implemented as one or more processors, e.g., computers. 
     When implemented in software the components include code, which when executed by the processor  802 , configure the processor  802  to implement the function corresponding to the component. In embodiments where the assembly of components  900  is stored in the memory  810 , the memory  810  is a computer program product comprising a computer readable medium comprising code, e.g., individual code for each component, for causing at least one computer, e.g., processor  802 , to implement the functions to which the components correspond. 
     Completely hardware based or completely software based components may be used. However, it should be appreciated that any combination of software and hardware, e.g., circuit implemented components may be used to implement the functions. As should be appreciated, the components illustrated in  FIG. 9  control and/or configure the repeater  800 , or elements therein such as the processor  802 , to perform the functions of corresponding steps illustrated and/or described in the method of one or more of the flowcharts, signaling diagrams and/or described with respect to any of the Figures. Thus the assembly of components  900  includes various components that perform functions of corresponding one or more described and/or illustrated steps of an exemplary method, e.g., steps of the method of flowchart  700  of  FIG. 7  and/or described or shown with respect to any of the other figures. 
     Assembly of components  900  includes a component  904  configured to store a codebook including uplink mode information including serving and nulling weights for a plurality of different antenna beam arrangements, and a component  906  configured to detect TDD timing schedule including a plurality of times at which a switch is made between uplink and downlink communications. Component  906  includes a component  908  configured to operate a repeater to receive at least one of a system information broadcast (SIB) or a slot format information (SFI) broadcast, a component  910  configured to decide the received at least one of the SIB or the SFI broadcast to recover TDD timing information, a component  912  configured to monitor for at least one gap in base station (BS) and user equipment (UE) transmissions. Component  912  includes a component  913  configured to detect a gap. Assembly of components  900  further includes a component  914  configured to determine if uplink or downlink communications preceded the gap, e.g. a gap detected during the monitoring. The set of components  900  also includes, in some embodiments, a side channel information detection component  915  configured to detect uplink/downlink schedule information and/or other repeater control information that can be and sometimes is received via a side communications channel, e.g., a channel that is not used for communicating data or control information between a base station and UE. The side channel maybe a wireless side channel or a wired side channel. The side channel is not used in all embodiments and in cases where a wireless side channel or other side channel is not used component  915 , may be and sometimes, is omitted from the repeater. 
     Assembly of components  900  further includes a component  916  configured to monitor current time and detect a transition in accordance with the TDD timing schedule. Component  916  includes a component  918  configured to detect a transition from an uplink mode of operation to a downlink mode of operation in accordance with the recovered TDD timing information and a component  920  configured to detect a transition from a downlink mode of operation to an uplink mode of operation in accordance with the recovered TDD timing information. 
     Assembly of components  900  further includes a component  922  configured to control operation as a function of the determination if uplink or downlink transmissions preceded the detected gap, a component  924  configured to detect a transition from an uplink mode of operation to a downlink mode of operation, e.g. in response to detecting a gap and determining the uplink signals preceded the gap, and a component  926  configured to detect a transition from a downlink mode of operation to an uplink mode of operation, e.g. in response to detecting a gap and determining the downlink signals preceded the gap. 
     Assembly of components  900  further includes a component  932  configured to set a first set of donor side antenna receiver weights to a first set of values which causes constructive signal cancellation when combining signals received from donor side receive antenna output of a donor side antenna and a component  934  configured to decrease the gain or a donor side receiver amplifier by decreasing a voltage supplied to the donor side receiver amplifier or by decreasing a bias current supplied to the donor side receiver amplifier. Component  934  includes a component  936  configured to reduce the voltage supplied to the amplifier to a lower voltage than a voltage with is supplied during the downlink mode of operation. 
     Assembly of components  900  further includes a component  938  configured to set the first set of antenna donor side antenna receiver weights to a second set of values used during said downlink mode of operation, said second set of values differing from said first set of values in terms of phase components but not in terms of amplitude components, and a component  940  configured to increase the gain of a donor side receiver amplifier by increasing a voltage supplied to the donor side receiver amplifier or by increasing a bias current supplied to the donor side receiver amplifier. Component  940  includes a component  942  configured to increase the voltage supplied to the amplifier to a higher voltage than a voltage which is supplied during said uplink mode of operation. 
     Assembly of components  900  further includes a component  944  configured to control a donor side switch to change between a transmit and receive position based on the TDD timing schedule, and a component  946  configured to operate a repeater to receive a signal and re-transmit said signal in accordance with a set of control information including switch setting, antenna weights and antenna gains. Component  946  includes a component  948  configured to operate said repeater to receive said signal and re-transmit said signal in accordance with the set of control information including switch setting, antenna weights and antenna gains without performing decoding/encoding and/or decrypting/encrypting operations. In some embodiments component  948  automatically controls which of a plurality of antenna weights is used and in some cases automatically selects based on the set of control information which of a plurality of donor side antenna weights are used at a given time, e.g., based on the TDD timing schedule. Component  948  includes a component configured to use a beam which is narrower for the donor side communications (base station/repeater communications) than for service side communications (repeater/user equipment communications). 
       FIG. 10  is a diagram  1000  showing a set  1008  of timing diagrams for autonomous TDD switch detection at a repeater  1004  with elements of the system being shown on the left, timing diagram corresponding to the element (gNB)  1002 , Repeater  1004  and UE  1006 , being shown on the right and the timing scale being consistent between the different elements as time progresses from the left side to the right side of the timing diagrams which are aligned to help understanding of the timing relationship between the operation of the different components. Timing diagram  1010  relates to gNB, e.g., base station, operation. Timing diagram  1012  relates to repeater operation and timing diagram  1014  relates to operation of the UE  1006  which maybe and sometimes is the use furthest form the gNB  1002  and which is being services via the repeater  1004  which maybe and sometimes is a repeater implemented in accordance with the invention such as one or the repeaters shown in the one or more of the other figures of the application. In  FIG. 10  the set of timing diagrams  1008  includes a timing diagram corresponding to the base station  1002 , e.g., gNB, which includes a downlink transmission TX time period  1016  followed by a switching time period  1030  in which a switch from downlink transmission at the gNB to uplink mode of operation is implemented. In addition to the switching period  1030  there is a gap period GAP  1   1002  during which the base station  1002  refrains from transmitting, The total gap between the point at which the switch from uplink to downlink operation has a time duration of GAP  1  plus S where S is the time  1030  in which the switch is made. The switch and gap periods are followed at the base station by an uplink transmission period  1018 ″ which is followed by another switching period  1030  in which the base station switches from uplink back to downlink transmission mode with downlink transmissions then occurring in the downlink transmission period  1020 . 
     The repeater  1004  is some distance away from the base station  1004  and will receive the downlink signals transmitted by the base station  1012  in the downlink Tx period  1016 ′ and retransmit these signals received at the donor side receiver to the UE devices via the repeaters service side transmitter. During the detect and switch period  1036 , the repeater can and will detect the falloff, e.g., stopping, of signals from the base station  1002  and interpret that as an indication that there is a switch to uplink TX mode which is occurring. The repeater than operates during uplink TX mode  1018 ′ in uplink mode retransmitting the signals received from the service side receiver(s), e.g., from one or more UE devices via the donor side transmitter(s) of the repeater without the signals being decoded. The silence period  1030 ′ in which switching to downlink transmission mode occurs at the base station is detected by the repeater during period  1038  based on the fall off of UE signals that are being received for retransmission. During period  1038  the repeater  1004  switches back to downlink mode of operation with signals being received from the base station  1002  being transmitted to the UE and/or other CPE devices within coverage are of the repeater  1004 . The set of gains and weights used for controlling signal amplification and/or combining maybe and sometimes are obtained from memory based on the uplink or downlink mode of operation being implemented at the repeater  1004  and/or the antenna array beam pattern being used during the uplink/downlink mode of operation that is implemented based on the mode of operation determined based on the received signals. 
     The last timing diagram  1014  of  FIG. 10  shows the timing sequence at a UE, e.g., furthest from the base station  1002 . The UE  1006  is likely to receive signals transmitted by the service side of the repeater  1004  in addition to the original signals from the gNB. The signals maybe treated by the UE as multipath signals with the UE being unaware that some of the signals are from the repeater transmission. It should be appreciated that the signal from the gNB and repeated signal transmitted by the UE will both be received in at least some embodiments within a cyclic prefix time period an easily processed without the UE having to know of the presence of the repeater  1004 . 
     UE timing diagram  1014  includes a downlink time period  1016 ″ in which downlink signals from the base station  1002  and repeater  1004  are received and combined followed by switching period  1030 ′ which is then followed by an uplink transmission time period  1018  which has a starting point in time  1037  determined by a timing advance signal from the base station  1002  which is directed to UE  1006 . As with the UE the base station need not know of the presence of the repeater and timing controls the individual UEs but does not send individual timing advance signals to individual repeaters. Following the uplink transmission period  1018  in which the UE  1006  transmits to the base station  1002  the UE  1006  remains silent, e.g., while other UEs transmit to the base station. The UE then resumes downlink operation for time period  1020  in which it receives signals transmitted by both the base station  1002  and repeater  1004  transmit to the UE  1006 . 
     Various aspects of the invention relate to repeater stability will now be described. From a terminology perspective, the repeater has two sides to it, the side facing the infrastructure, e.g., a base station, which is called donor-side and the side facing the device, (e.g, User Equipment device or customer premises equipment (CPE)), which is called service-side. The goal of a bi-directional repeater is to receive from the donor (service) side, amplify and then retransmit the signal on the service (donor) side during downlink operation of the system so that CPEs receive signals from the base station and to receive from the service side, amplify and then retransmit the signal on the donor side during uplink operation of the system so that the base station receives signals from the CPE devices. 
     Repeaters face the issue of stability due to signal leakage/self-interference. Consider the forward path where the donor-side signal is received, amplified and transmitted on the service side. In this case since a receive operation (from the donor) happens simultaneously with a transmit operation (to the final receiver), there is a risk of the transmit signal leaking back into the receiver, over-the-air. This creates a feedback loop that can be guaranteed to be stable if the gain in the signal path is smaller than the reciprocal of the gain in the feedback path—in other words, the gain that the repeater can operate at is bounded by the attenuation from the service side transmitter antenna to the donor side receive antenna. The repeater maybe unstable if this is not the case. Consider for example, if the target gain for the repeater is say 80 dB, then the attenuation of the signal from the service side transmitter antenna to the donor side receiver antenna must be at least 80 dB or better for the repeater to be stable. By instability we mean that for a finite input signal level into the repeater, the output level will gradually keep increasing indefinitely, causing output circuits to saturate and output signals to distort significantly. A primary method of ensuring stability is by trying to isolate the two antennas from each other, either by physically separating them and/or shielding them from each other to reduce the leakage. Other methods, such as active cancellation of the leakage, may be needed in certain situations. 
     Another source of interference is the donor-to-donor side and service-to-service side transmitter-to-receiver interference (we will call this ‘same-side’ or ‘duplexing’ interference). This is typically handled by a duplexing constraint and is not unique to repeaters. However, the level of ‘same-side’ interference does impact the maximum gain of the repeater and is therefore coupled. Note that even though each of the donor and service sides depict a separate Tx and Rx, this model is equally valid for common Tx and Rx antenna on each side. 
     Even if there is perfect isolation between the donor and service sides, the presence of ‘same-side’ interference will still limit the maximum gain of the repeater for which stability is preserved. Typical duplexing methods are frequency division duplexing (FDD), time division duplexing (TDD) and full duplex (FD). 
     In FDD, the transmit and receive signals on the same-side of the repeater would be separated by a fairly large frequency separation. Furthermore, filters maybe and sometimes are used to cut-off unwanted interference from transmitter to receiver. Such filtering could typically accomplished using an RF device called a duplexer. 
     In TDD systems, the same frequency band or channel is used for both transmit and receive operation but they are done at different times. Switching between transmit mode and receive mode is done at well-defined times, usually announced and managed by the base station. The T/R switch manages which signal path is connected at any given time. In real world conditions the T/R switch will not provide perfect isolation between the paths. 
     In Full Duplex (FD) repeaters, transmission and reception happens simultaneously in the same band. A three-port RF device called the circulator may be used to separate out the transmit and receive paths. A circulator would allow signal to flow from Port 1 to Port 2 but not Port 3 and similarly from Port 2 to Port 3 but not port 1 and port 3 to port 1, but not port 2. Since the device will not perfectly suppress signal going into the undesired port, some leakage may be expected from imperfect isolation. In single-antenna systems this typically requires active interference cancellation of the residual leakage. 
     It is important to note that a TDD repeater wherein the repeater does NOT have knowledge of the underlying TDD structure, can be implemented like an FD repeater. 
     In some but not all embodiments of the present invention the TDD structure is learnt at the repeater and then exploited to avoid unnecessarily building or using a FD repeater. 
     Various aspects related to Millimeter Wave Repeaters will now be described. The repeaters of the present invention are in many embodiments Millimeter Wave Repeaters. The main difference between repeaters for millimeter wave systems and those for sub-6 GHz systems is that millimeter wave systems use antenna arrays for communication. Antenna arrays allow the formation of beams which allow the signal to be focused in the direction of interest, thereby overcoming some of the propagation challenges at these frequencies. In various embodiments a millimeter wave repeater will have separate antenna arrays for the donor and service sides. For example, the donor-side antenna array could be of size 256 antenna elements and so can the service side. 
     In addition to the modes of interference present in a single-antenna system discussed earlier in this document, there is over-the-air interference between the ‘same-side’ antenna elements that needs to be dealt with in millimeter wave systems. If the same array is used for transmit and receive, then in some embodiments we replicate the single antenna structures. This architecture, while compact, can lead to a high ‘same-side’ self-interference. Another approach used in some embodiments is to use different arrays for transmit and receive on each of the donor and receive sides. 
     Most 5G millimeter wave deployments as well as the 802.11 deployments are expected to be TDD. If the TDD structure is known at the receiver, then it can be exploited to reduce the extent of self-interference in both the common and separate antenna configurations. 
     The one advantage of a common antenna structure is that it requires much less hardware compared to the separate antenna structures. The main disadvantage is that the elements within each array have to be placed fairly close to each other to achieve beamforming gain—typically, they would be placed half a wavelength apart, which at 30 GHz frequency comes out to be around 0.5 cm. Clearly, a close placement like that would make the over-the-air coupling and resultant interference to be fairly high. Use of multiple separate antenna structures allows the transmit and receive array to be placed on each side of the repeater a little bit further away (several centimeters away) from each other, thereby reducing the extent of coupling and self-interference as compared to other implementations. Each array can then respect its requirement for half-wavelength separation between its elements. One disadvantage of the separate array approach is of course that it requires double the number of elements and some of the associated RF circuitry would also require duplication. 
     In both approaches, the interference mitigation, in accordance with the invention can be enhanced by using the antenna weights to null the self-interference, e.g. with the weights being determined from a look up table or tables for a given mode of operation. 
     In this figure, when downlink traffic is flowing (e.g., when the donor will receive (Rx), and the service side will transmit (Tx), the weights on the service Rx antennas can be selected to null the interference. Taken together with the switch isolation, this can provide substantial reduction in self-interference. This can and is done in some embodiments when the TDD structure is known. In such an embodiment the weights that are sued will alternate between the ‘nulling’ weights and the ‘beam forming’ weights depending on whether downlink or uplink operations is being supported at a given time. 
     Let&#39;s assume downlink flow of data and so the weights we select to null will be on the service Rx antennas. Let hi, be the effective channel response on service Rx antenna i from service Tx antenna j. The reason this is called ‘effective’ channel is because it is the product of the weight chosen on service Tx antenna j and the actual channel coefficient. The transmitted signal prior to weight application on each of the antennas is the same and therefore, the signal at the output of the service Rx antenna combiner is w1s*(h1,1+h1,2)*s+w2s*(h2,1+h2,2)*s. This can be set to zero by arbitrarily assigning one weight to unity and selecting the second weight so that the above weighted sum yields zero. Note that this will be true regardless of the sample s. In practice, one can select balanced weights, rather than select one to be unity. Note that this method extends to any number of antennas, not just two. Also, it is assumed here that the effective channel coefficients are computed through offline calibration. 
     This can be set to zero by arbitrarily assigning one weight to unity and selecting the second weight so that the above weighted sum yields zero. Note that this will be true regardless of the sample s. In practice, one can select balanced weights, rather than select one to be unity. Note that this method extends to any number of antennas, not just two. Also, it is assumed here that the effective channel coefficients are computed through offline calibration. 
     In addition to (a) separating antennas for Tx and Rx (b) exploiting the TDD structure to switch paths on and off as needed (c) using antenna weights to null the self-interference, active cancellation as shown for the full-duplex repeater case can be, and is, undertaken to further reduce the interference in some embodiments. Furthermore, optionally, the amplifier gain in the unused direction can be turned down to almost zero gain thereby reducing or minimizing the feedback interference. In addition or alternatively, the supply voltage to the power amplifiers in the unused direction can be and sometimes is cut to further reduce feedback interference. 
     While the power can be changed to the amplifiers in the direction in which transmission is to be avoided, in some embodiments power to the amplifiers in both directions is held control is achieved by controlling the gain or other weights used in the transmit or receive side to minimize or avoid interference to the side of the repeater which is in use for the base station or device facing portions of the repeater. 
     Thus, it should be appreciated that knowledge of the TDD structure at the repeater can be used to effectively manage the self-interference and thereby operate the repeater at very high stable gain. 
     One simple method to obtain information about the TDD structure that is used in some embodiments to decide how to control the repeater during a given time period is for the base station, e.g., gNB, to inform the repeater of the upcoming structure. In some LTE embodiments for example, the structure is a repeating pattern over a 1 ms interval and the LTE standard specifies an allowed set of patterns to select from. This information of which of the TDD patterns is to be used at a given time is provided by the base station in a broadcast message (called SIB). In various embodiments the TDD structure message, e.g., SIB, is received and decode by the repeater to learn the TDD structure. Similar mechanisms are available in 5G NR standard that may be exploited to learn the TDD structure. If the TDD configuration is not conveyed through an existing SIB message, then a new SIB message may be sent, in accordance with some embodiments, with a message ID that is outside the range of values supported in the exiting specification thereby allowing the repeater of the present invention to recognize and understand the information in the new message providing the TDD structure information. Such an approach will not result in any improper behavior on UEs as they will just ignore the SIB message with the message ID that they are not to use or do not understand. Another method to inform the repeater of the invention of the TDD timing structure, that is used in some embodiments is to define and communicate an RNTI (a radio network temporary identifier) from the base station that is unique to repeaters and send the SIB message on this RNTI. UEs will not know this RNTI and as a result will discard a control channel message received with this RNTI. Yet another approach that is used in some embodiments is to provide the TDD timing structure information to the repeaters of the invention via an out-of-band side channel or have the repeater retrieve this information from a data base, e.g., at regular intervals. The side channel could be via LTE or some other wired or wireless communications channel. 
     There are some issues with relying on SIB or SIB-like signaling to communicate the TDD structure. Firstly, it may require the operator, e.g., base station operator, and base station (e.g. gNB) vendor to support the signaling. Often times the repeater is deployed by private parties, with operator certification, and the operator may not get involved at all. Secondly, the 5G NR standard allows for a much more dynamic TDD structure that is determined on the fly, rather than specified via configuration. In such cases, it is desirable for the repeater to autonomously learn the TDD switching structure. Support for autonomous learning of the TDD structure is included in some but not necessarily all embodiments. 
     In TDD systems a switch from downlink to uplink and vice-versa is preceded by a gap, which in a standard is typically represented by one or more blank symbols. Consider for example the gap shown in  FIG. 10 . The gap is intended to accommodate switching times at the transmitter and receiver and to allow for round-trip delay between the gNB and UE. The latter is because the UE needs to advance its timing as needed to arrive at the expected time at the gNB (whose time is regarded as fixed and golden). So, a UE who is close to the gNB will see smaller propagation delay and hence would not need to advance its timing on the uplink. 
     The method for gap detection at the repeater implemented in accordance with the invention, is to detect that the signal being received in a particular direction (i.e. downlink or uplink) has suddenly dropped substantially. Since the signal level drop at the edge of switch is substantial this detection should be relatively easy to make and not require substantial amount of noise averaging. Also, the switches will coincide with a symbol boundary and this information can be exploited as well to discover a switch. Accordingly, by monitoring signal levels at the repeater and recognizing a gap, switches between uplink and downlink operation can be detected and the repeater can switch so that it operates in the appropriate mode of operation given a detected switch in transmission directions. 
     Another aspect that is addresses with millimeter wave repeaters is beam management on both the donor and service sides of the link. The protocols used in both 5G and 802.11ad/ay systems for beam management are fundamentally based on beam sweeps at transmitter and receiver, followed by feedback signaling to execute a change in beams as needed. Note that often times transmit and receive beams are paired, and therefore, beam change would entail changing both beams synchronously. 
     Donor Side Beam Management 
     Initial Procedure: In 5G NR, the gNB sweeps the synchronization signal with regular periodicity. Each transmission of the synchronization signal is called a Synchronization Signal Block (SS Block). This is used by UEs to first acquire the downlink and lock in time, frequency and best beam. In addition to making measurements on each swept base station beam, the UE too sweeps through its receive beams to determine the best beam pair i.e. the best gNB transmit beam and the corresponding best UE receive beam. When the UE wants to establish a connection with the gNB, this is usually followed by a beamformed random access procedure. Once the connection is established, the gNB and UE typically use unicast signaling to measure, report and maintain or change as dictated by system dynamics. 
     A repeater in accordance with some aspects of the invention in some embodiments processes the swept SS blocks and its codebook of Rx beams in the same or similar way as a UE would for initial acquisition. From the set of Rx beams, the repeater selects the best and sets it to that value. The chosen Rx beam will also be used as the Tx beam for transmitting to the base station, e.g., gNB. 
     It is expected that the repeater will not be mobile and as a result the best donor side Tx and Rx beams are unlikely to change. The repeater could have multiple processing chains and therefore candidate Rx beams can be regularly scanned on one processing chain while one is locked on to the serving Rx beam. The candidate beam processing could discover that a better Rx beam than the one currently being used also requires the gNB&#39;s Tx beam to change. There are three alternative ways to deal with this that are used in various embodiments:
         1. In-band signaling from repeater to gNB.   2. Out-of-band signaling from repeater to gNB   3. Autonomous adaptation at the repeater to effect this beam change via the UE.       

     In-band signaling from the repeater to gNB to execute beam changes can add significant complexity to the repeater. The repeater will have to behave like a UE on the donor link at least for the purpose of beam management. This would imply that upon acquisition, the repeater should send a random-access signal to the gNB to establish a connection and get an ID from the gNB. Subsequently, it will monitor the downlink control channel and send uplink control channels as required by 5G spec to execute beam management. During these periods, it will send uplink traffic that arrived over the service side link from UE and therefore, has to perform a multiplexing task. 
     Out-of-band signaling using a sub-6 GHz technology like LTE from repeater to gNB using special-purpose messaging as an application layer packet in LTE is another approach used in some embodiments. Upon receiving the Tx beam-change request from the repeater, the gNB can start offering the new beam in reference signals to the UE and ultimately, change the Tx beam in a timed manner. This is effectively the same protocol that would happen for a beam change between the gNB and the UE but involves the additional step of informing the repeater of the change ahead of time, so that the repeater can set its Rx beam correctly for the new gNB Tx beam. 
     Autonomous adaptation at the repeater of the Rx beam can eventually force the gNB to change its Tx beam. However, if the repeater switches the Rx beam suddenly, then that could cause the link to the UE to drop drastically resulting in temporary outage. The UE will eventually recover because it will find the new beam pair on the SS block sweep that is constantly undertaken by the gNB. Another approach would be for the repeater to use the weighted sum of the signals from the old and new Rx beams for a period of time to effect a soft transition. During this period, the normal beam sweep process at the gNB and UE will find the new beam pair and transition to it. However, the repeater will not have precise knowledge of the transition time and errors could occur in the process. Recovering from these errors is still feasible as the SS block sweep will eventually settle on the new beam pair. 
     For donor-side repeater transmissions, it is expected that reciprocity would be used, at least in some embodiments, to use the discovered Rx beam for Tx as well. This is a fairly standard assumption that is also made by the UE, in the non-repeater mode of operation. 
     Service Side Beam Management 
     On the service side (e.g. CPE device facing side), ideally the repeater should support fixed beams and repeat the received signal from the gNB on those beams simultaneously. This helps keep the repeater complexity low as it doesn&#39;t the repeater to implement per UE beam management protocols specified in 3GPP. The disadvantages of the fixed beams approach are that (a) beamforming gain cannot always be maximized to the UE and (b) number of beams needed could be large to cover the area with fixed beams while maintaining adequate minimum gain. By using higher power power amplifiers (PAs), beam broadening can be employed to efficiently tradeoff the number of beams that can be deployed on the service side with the minimum beamforming gain. 
     Exemplary Numbered Method Embodiments 
     Method embodiment 1. A method of operating a repeater comprising: detecting ( 706 ) a time division duplex (TDD) timing schedule including a plurality of times at which a switch is made between uplink and downlink communication; and controlling ( 744 ) a donor side switch (T/R switch) to change between a transmit position and a receive position based on the TDD timing schedule. 
     Method embodiment 1A. The method of Method embodiment 1, wherein said switch is a first transmit/receive switch that couples a first donor side antenna element to a first uplink signal path or a first downlink signal path at a given time. 
     Method embodiment 1B. The method of Method embodiment 1, wherein said switch is a donor side uplink switch that couples a donor side transmit antenna element to a first uplink signal path. 
     Method embodiment 2. The method of Method embodiment 1 wherein detecting ( 706 ) the TDD timing schedule includes: receiving ( 708 ) at least one of a system information broadcast (SIB) or a slot format indication (SFI) broadcast; and decoding ( 710 ) the received at least one of the SIB (system information broadcast) or SFI (slot format indication) broadcast to recover TDD timing information. 
     Method embodiment 2A. The method of Method embodiment 1, wherein detecting ( 706 ) the TDD timing schedule includes monitoring ( 712 ) for at least one gap in base station (BS) and user equipment (UE) transmissions; and determining ( 714 ) if uplink or downlink signals preceded said gap. 
     Method embodiment 2B. The method of Method embodiment 2A, further comprising: detecting ( 724 ) a transition from an uplink mode of operation to a downlink mode of operation when it is determined that uplink signals preceded a detected gap. 
     Method embodiment 2C. The method of Method embodiment 1 wherein detecting the TDD schedule includes receiving TDD schedule information communicated to the repeater in a side channel used to communicate TDD schedule information to said repeater. 
     Method embodiment 2D. The method of Method embodiment 2C wherein said side channel is different from communications channels used to provide system information to UE devices or to communicate user data to UE devices. 
     Method embodiment 3. The method of Method embodiment 2, further comprising: (e.g., uplink data case) when said TDD timing schedule indicates a change from a downlink mode of operation to an uplink mode of operation, setting ( 732 ) a first set of donor side antenna receiver weights to a first set of values which cause constructive signal cancelation when combining signals received from donor side receive antenna outputs of a donor side antenna. 
     Method embodiment 3A. The method of Method embodiment 3, wherein said first set of donor side antenna receiver weights is a set of weights, each weight including an amplitude component and a corresponding phase component; and wherein said first set of values differs from a second set of values used during said downlink mode of operation. 
     Method embodiment 3AA. The method of Method embodiment 3A, wherein the values differ in terms of phase components but not amplitude components. 
     Method embodiment 3AAA. The method of Method embodiment 3A, wherein the values differ in terms of amplitude components but not phase components. 
     Method embodiment 4. The method of Method embodiment 2, further comprising: when said TDD timing schedule indicates a change from a downlink mode of operation to an uplink mode of operation, further performing the step of: ii) decreasing ( 734 ) the gain of a donor side receiver amplifier. 
     Method embodiment 4A. The method of Method embodiment 4, wherein decreasing ( 734 ) the gain of the donor side receiver amplifier is implemented by decreasing a voltage supplied to the donor side receiver amplifier or by decreasing a bias current supplied to the donor side receiver amplifier. 
     Method embodiment 5. The method of Method embodiment 4, wherein decreasing ( 734 ) the gain of the donor side receive amplifier includes reducing ( 736 ) said the voltage supplied to the amplifier to a lower voltage than a voltage which is supplied during downlink mode operation. 
     Method embodiment 6. The method of Method embodiment 5, wherein said lower voltage is a non-zero voltage. 
     Method embodiment 7. The method of Method embodiment 5, wherein said lower voltage is a zero voltage. 
     Method embodiment 8 The method of Method embodiment 1, further comprising using ( 750 ) a beam which is narrower for donor side communications than service side communications. 
     Method embodiment 9. The method of Method embodiment 8 further comprising storing ( 704 ) a code book including uplink mode information including serving and nulling weights for a plurality of different antenna beam arrangements. 
     Method embodiment 10. The method of Method embodiment 1, further comprising: automatically select ( 738 ) which set of donor side antenna weights is to be used at a given time based on the TDD timing schedule. 
     Exemplary Numbered Apparatus Embodiments 
     Apparatus embodiment 1: A repeater ( 106  or  600  or  800 ) comprising: a memory ( 611  or  810 ); and a processor ( 601  or  802 ) coupled to said memory, the processor being configured to: detect ( 706 ) a time division duplex (TDD) timing schedule including a plurality of times at which a switch is made between uplink and downlink communication; and control ( 744 ) a donor side switch (T/R switch) ( 258  or  260  or  306  or  308 ) to change between a transmit position and a receive position based on the TDD timing schedule. 
     Apparatus embodiment 1A. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 1, wherein said switch ( 306  or  308 ) is a first transmit/receive switch that couples a first donor side antenna element ( 302  or  304 ) to a first uplink signal path or a first downlink signal path at a given time. 
     Apparatus embodiment 1B. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 1, wherein said switch ( 258  or  260 ) is a donor side uplink switch that couples a donor side transmit antenna element ( 262  or  264 ) to a first uplink signal path. 
     Apparatus embodiment 2. The repeater ( 106  or  600  or  802 ) of Apparatus embodiment 1 wherein the processor ( 601  or  802 ) is configured, as part of detecting ( 706 ) the TDD timing schedule, to: receive ( 708 ) at least one of a system information broadcast (SIB) or a slot format indication (SFI) broadcast; and decode ( 710 ) the received at least one of the SIB (system information broadcast) or SFI (slot format indication) broadcast to recover TDD timing information. 
     Apparatus embodiment 2A. The repeater ( 106  or  600  or  802 ) of Apparatus embodiment 1, wherein the processor ( 601  or  802 ) is further configured, as part of detecting ( 706 ) the TDD timing schedule to: monitor ( 712 ) for at least one gap in base station (BS) and user equipment (UE) transmissions; and determine ( 714 ) if uplink or downlink signals preceded said gap. 
     Apparatus embodiment 2B. The repeater ( 106  or  600  or  802 ) of Apparatus embodiment 2A, wherein the processor ( 601  or  802 ) is further configured to: detect ( 724 ) a transition from an uplink mode of operation to a downlink mode of operation when it is determined that uplink signals preceded a detected gap. 
     Apparatus embodiment 2C. The repeater of Apparatus embodiment 1 wherein the processor is further configured to detect the TDD TDD schedule by receiving information communicated to the repeater in a side channel used to communicate TDD schedule information. 
     Apparatus embodiment 2D. The method of Apparatus embodiment 2C wherein said side channel is different from communications channels used to provide system information to UE devices or to communicate user data to UE devices. 
     Apparatus embodiment 3. The repeater ( 106  or  600  or  802 ) of Apparatus embodiment 2, when said TDD timing schedule indicates a change from a downlink mode of operation to an uplink mode of operation, setting ( 732 ) a first set of donor side antenna receiver weights to a first set of values which cause constructive signal cancelation when combining signals received from donor side receive antenna outputs of a donor side antenna. 
     Apparatus embodiment 3A. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 3, wherein said first set of donor side antenna receiver weights is a set of weights stored in said memory ( 611  or  810 ), each weight including an amplitude component and a corresponding phase component; and wherein said first set of values differs from a second set of values used during said downlink mode of operation. 
     Apparatus embodiment 3AA. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 3A, wherein the values differ in terms of phase components but not amplitude components. 
     Apparatus embodiment 3AAA. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 3A, wherein the values differ in terms of amplitude components but not phase components. 
     Apparatus embodiment 4. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 2, further comprising: a donor side receiver amplifier ( 206  or  208  or  310  or  312 ); and when said TDD timing schedule indicates a change from a downlink mode of operation to an uplink mode of operation, the processor ( 601  or  802 ) being further configured to control the repeater ( 106  or  600  or  800 ) to: decrease ( 734 ) the gain of a donor side receiver amplifier ( 206  or  208  or  310  or  312 ). 
     Apparatus embodiment 4A. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 4, wherein decreasing ( 734 ) the gain of the donor side receiver amplifier is implemented by decreasing a voltage supplied to the donor side receiver amplifier or by decreasing a bias current supplied to the donor side receiver amplifier.). 
     Apparatus embodiment 5. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 4, wherein decreasing ( 734 ) the gain of the donor side receive amplifier includes reducing ( 736 ) said the voltage supplied to the amplifier to a lower voltage than a voltage which is supplied during downlink mode operation. 
     Apparatus embodiment 6. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 5, wherein said lower voltage is a non-zero voltage. 
     Apparatus embodiment 7. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 5, wherein said lower voltage is a zero voltage. 
     Apparatus embodiment 8 The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 1, further comprising using ( 750 ) a beam which is narrower for donor side communications than service side communications. 
     Apparatus embodiment 9. The repeater ( 106  or  600  or  800 ) of Apparatus embodiment 8 further comprising: a code book ( 842  or  400  or  500 ) stored in said memory ( 611  or  810 ) including uplink mode information including serving and nulling weights for a plurality of different antenna beam arrangements. 
     Apparatus embodiment 10. The repeater of Apparatus embodiment 1, wherein the processor ( 601  or  802 ) is further configured to: automatically select which set of donor side antenna weights is to be used at a given time based on the TDD timing schedule. 
     In the present application base stations are to be understood as including access points while wireless terminals will be used to refer to devices which interact with base stations, e.g., UE devices which interact with access points, e.g., WiFi STAs (stations). Wireless terminals such as UEs can be, for example, cell phones, tablets, mobile or stationary customer premises equipment. A communications device can be either base stations or wireless terminals. 
     The techniques of various embodiments may be implemented using software, hardware and/or a combination of software and hardware. Various embodiments are directed to apparatus and/or systems, e.g., wireless communications systems, wireless terminals, user equipment (UE) devices, access points, e.g., a WiFi wireless access point, a cellular wireless AP, e.g., an eNB or gNB, user equipment (UE) devices, a wireless cellular systems, e.g., a cellular system, WiFi networks, etc. Various embodiments are also directed to methods, e.g., method of controlling and/or operating a system or device, e.g., a communications system, an access point, a base station, a wireless terminal, a UE device, etc. Various embodiments are also directed to machine, e.g., computer, readable medium, e.g., ROM, RAM, CDs, hard discs, etc., which include machine readable instructions for controlling a machine to implement one or more steps of a method. The computer readable medium is, e.g., non-transitory computer readable medium. 
     It is understood that the specific order or hierarchy of steps in the processes and methods disclosed is an example of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes and methods may be rearranged while remaining within the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented. In some embodiments, one or more processors are used to carry out one or more steps of the each of the described methods. 
     In various embodiments each of the steps or elements of a method are implemented using one or more processors. In some embodiments, each of elements or steps are implemented using hardware circuitry. 
     In various embodiments nodes and/or elements described herein are implemented using one or more components to perform the steps corresponding to one or more methods, for example, controlling, establishing, generating a message, message reception, signal processing, sending, communicating, e.g., receiving and transmitting, comparing, making a decision, selecting, making a determination, modifying, controlling determining and/or transmission steps. Thus, in some embodiments various features are implemented using components or in some embodiments logic such as for example logic circuits. Such components may be implemented using software, hardware or a combination of software and hardware. Many of the above described methods or method steps can be implemented using machine executable instructions, such as software, included in a machine readable medium such as a memory device, e.g., RAM, floppy disk, etc. to control a machine, e.g., general purpose computer with or without additional hardware, to implement all or portions of the above described methods, e.g., in one or more nodes. Accordingly, among other things, various embodiments are directed to a machine-readable medium, e.g., a non-transitory computer readable medium, including machine executable instructions for causing a machine, e.g., processor and associated hardware, to perform one or more of the steps of the above-described method(s). Some embodiments are directed to a device, e.g., a wireless communications device including a multi-element antenna array supporting beam forming, such as a cellular AP or Wifi AP, a wireless terminal, a UE device, etc., including a processor configured to implement one, multiple or all of the steps of one or more methods of the invention. 
     In some embodiments, the processor or processors, e.g., CPUs, of one or more devices, are configured to perform the steps of the methods described as being performed by the devices, e.g., communication nodes. The configuration of the processor may be achieved by using one or more components, e.g., software components, to control processor configuration and/or by including hardware in the processor, e.g., hardware components, to perform the recited steps and/or control processor configuration. Accordingly, some but not all embodiments are directed to a device, e.g., access point, with a processor which includes a component corresponding to each of the steps of the various described methods performed by the device in which the processor is included. In some but not all embodiments a device, e.g., wireless communications node such as an access point or base station, includes a component corresponding to each of the steps of the various described methods performed by the device in which the processor is included. The components may be implemented using software and/or hardware. 
     Some embodiments are directed to a computer program product comprising a computer-readable medium, e.g., a non-transitory computer-readable medium, comprising code for causing a computer, or multiple computers, to implement various functions, steps, acts and/or operations, e.g. one or more steps described above. Depending on the embodiment, the computer program product can, and sometimes does, include different code for each step to be performed. Thus, the computer program product may, and sometimes does, include code for each individual step of a method, e.g., a method of controlling a wireless communications device such as an access point. The code may be in the form of machine, e.g., computer, executable instructions stored on a computer-readable medium, e.g., a non-transitory computer-readable medium, such as a RAM (Random Access Memory), ROM (Read Only Memory) or other type of storage device. In addition to being directed to a computer program product, some embodiments are directed to a processor configured to implement one or more of the various functions, steps, acts and/or operations of one or more methods described above. Accordingly, some embodiments are directed to a processor, e.g., CPU, configured to implement some or all of the steps of the methods described herein. The processor may be for use in, e.g., a wireless communications device such as an access point described in the present application. 
     Numerous additional variations on the methods and apparatus of the various embodiments described above will be apparent to those skilled in the art in view of the above description. Such variations are to be considered within the scope. Numerous additional embodiments, within the scope of the present invention, will be apparent to those of ordinary skill in the art in view of the above description and the claims which follow. Such variations are to be considered within the scope of the invention.