Patent Publication Number: US-7899073-B2

Title: Methods and apparatus for monitoring for signals and selecting and/or using a communications band based on the monitoring results

Description:
FIELD 
     Various embodiments are directed to methods and apparatus for wireless communication and, more particularly, to methods and apparatus for use in peer to peer wireless communication. 
     BACKGROUND 
     In some WAN deployments communications band utilization varies somewhat through the WAN system. For example, different regions, cell, or cells may use different communications bands, different numbers of communications bands, and/or communications bands at different power levels. In some areas a WAN band which is allowed to be used by a service provider&#39;s network may go unused regarding WAN signaling due to infrastructure deployment considerations or current loading considerations. Thus available WAN air link resources can be, and sometimes are underutilized by the WAN signaling requirements at a given location and/or time. It would be advantageous if methods and apparatus were developed which allowed WAN air link resources to be used to support other communications techniques, e.g., peer to peer signaling. It would be beneficial if methods and apparatus were developed which facilitated identification of a WAN communications resource which could be utilized for peer to peer signaling, e.g., methods and apparatus which identify air link resources to be used for peer to peer signaling which have no or minimal impact to ongoing WAN communications. 
     SUMMARY 
     Methods and apparatus for supporting peer to peer communications are described. A plurality of wide area network communications bands in a wireless communications system are also available for use to communicate peer to peer signals. Some WAN bands may be, and sometimes are unused by a base station for WAN communications at a particular location. A peer to peer communications device monitors one or more WAN communications bands. Received signals in the monitored band or bands are compared to threshold criteria. In one embodiment, if the peer to peer communications device finds that no signal is detected in the monitored band or that the received evaluated signal from the monitored band is below a specified threshold level, then the peer to peer wireless terminal is allowed to use a band which is either the monitored band or a band corresponding to the monitored band for peer to peer signaling. 
     Various features are relevant to embodiments in which peer to peer signaling shares bandwidth with frequency division duplex (FDD) communications bands while other features are relevant to embodiments in which peer to peer signaling shares bandwidth with time division duplex (TDD) communications bands. Accordingly, it should be appreciated that not all features are used in all embodiments. 
     An exemplary method of operating a wireless communications device comprises: monitoring to receive a signal in at least one wide area network (WAN) communications band; and if no signal having a signal power level over a threshold level is received in a predetermined period of time from said communications band, selecting a corresponding communications band which corresponds to said monitored communications band, said selected corresponding band being selected for use in communicating a peer to peer signal. An exemplary wireless terminal in accordance with various embodiments comprises: a receiver module for receiving signals from at least one WAN communications band; a threshold determination module for determining if a signal having a signal power level over a threshold level is received in a predetermined period of time from said communications band; and a peer to peer communications band selection module for selecting a corresponding communications band, which corresponds to said monitored communications band, for peer to peer signaling, when said determination module determines that a signal having a signal power level over said threshold level is not received in the predetermined period of time. 
     While various embodiments have been discussed in the summary above, it should be appreciated that not necessarily all embodiments include the same features and some of the features described above are not necessary but can be desirable in some embodiments. Numerous additional features, embodiments and benefits are discussed in the detailed description which follows. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a drawing of an exemplary wireless communications system, an exemplary frequency spectrum partition, and a table identifying exemplary current wireless terminal frequency band usage. 
         FIG. 2  is a drawing including a plurality of sectorized base stations transmitting reference signals, and an exemplary peer to peer wireless terminal which receives and measures those reference signals. 
         FIG. 3  includes a drawing illustrating exemplary pairs of frequency bands in an exemplary frequency division duplex (FDD) wide area network (WAN) communications system which also supports peer to peer signaling, and a table illustrating exemplary peer to peer related information including exemplary selection criteria. 
         FIG. 4  includes a drawing illustrating exemplary pairs of frequency bands in an exemplary FDD WAN communications system which also supports peer to peer signaling, and a table illustrating exemplary peer to peer related information including exemplary selection criteria. 
         FIG. 5  illustrates an exemplary embodiment incorporating features represented by both  FIG. 3  and  FIG. 4 . 
         FIG. 6  is a drawing illustrating exemplary communications bands in a time division duplex (TDD) system where different cells using different TDD duplex bands, and wherein at least some of air link resources are shared between WAN and peer to peer communications. 
         FIG. 7  is a drawing illustrating exemplary communications bands in a time division duplex system where different cells use the same TDD bands but at different times, and wherein at least some of air link resources are shared between WAN and peer to peer communications. 
         FIG. 8  is a drawing illustrating an exemplary frequency band in a TDD WAN system in which the same frequency band corresponds to multiple uplink/downlink bands, and wherein at least some of the air link resources are shared with peer to peer communications. 
         FIG. 9  is a drawing of an exemplary communications system supporting WAN signaling and peer to peer signaling in accordance with various embodiments. 
         FIG. 10  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 11  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 12  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 13  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 14  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 15  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 16  is a flowchart of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. 
         FIG. 17  is a drawing of an exemplary wireless terminal, e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments. 
         FIG. 18  is a drawing of an exemplary wireless terminal, e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments 
         FIG. 19  is a drawing of an exemplary wireless terminal, e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a drawing  100  of an exemplary wireless communications system  102 , an exemplary frequency spectrum partition  104 , and a table  106  identifying exemplary current wireless terminal frequency band usage. Exemplary wireless communications system  102  supports both WAN communications, wherein a wireless terminal communicates via a base station attachment point with another wireless terminal in the system, and peer to peer communications, wherein a wireless terminal communicates with another wireless terminal without using a base station as a point of network attachment. 
     Exemplary wireless communications system  102  includes a plurality of base stations (base station  1   108 , base station  2   110 , base station  3   112 ) with corresponding cellular coverage areas (cell  1   114 , cell  2   116 , cell  3   118 ), respectively. In this example, the base stations are multi-sector base stations, e.g., 3 sector base stations. Cell  1   114  includes a first sector  120 , a second sector  122 , and a third sector  124 . Cell  2   116  includes a first sector  126 , a second sector  128 , and a third sector  130 . Cell  3   118  includes a first sector  132 , a second sector  134 , and a third sector  136 . In this system there is partial overlap between at least some of the sectors. 
     Frequency spectrum partition drawing  104  includes a first frequency band f 1    138 , a second frequency band f 2    140 , and a third frequency band f 3    142 . In some embodiments, the frequency bands ( 138 ,  140 ,  142 ) are downlink frequency bands. In some embodiments the frequency bands ( 138 ,  140 ,  142 ) are uplink frequency bands. In some embodiments a frequency band, e.g., frequency band f 1    138 , is used for both uplink and downlink in a TDD manner. In some embodiments a frequency band, e.g., frequency band f 1    138 , includes a FDD portion used for uplink and a FDD portion used for downlink. First frequency band f 1    138  is used for WAN signaling in first sectors ( 120 ,  126 ,  132 ) of cells ( 114 ,  116 ,  118 ), respectively. Second frequency band f 2    140  is used for WAN signaling in second sectors ( 122 ,  128 ,  134 ) of cells ( 114 ,  116 ,  118 ), respectively. Third frequency band f 3    142  is used for WAN signaling in third sectors ( 124 ,  130 ,  136 ) of cells ( 114 ,  116 ,  118 ), respectively. 
     The base stations ( 108 ,  110 ,  112 ) are coupled together and to other network nodes and/or the Internet via a backhaul. Exemplary system  102  includes network node  172  which is coupled to base stations ( 108 ,  110 ,  112 ) via network links ( 174 ,  176 ,  178 ), respectively. Network node  172  is also coupled to other networks nodes, e.g., other base stations, AAA nodes, home agent node, etc., and/or the Internet via network link  180 . Network links ( 174 ,  176 ,  178 ,  180 ) are, e.g., fiber optic links. 
     Exemplary communications system  102  includes a plurality of wide area network wireless terminals (MN  1   144 , MN  2   146 , MN  3   148 , and MN  4   150 ). MN  1   144  is coupled to a sector  2  base station  3  attachment point via wireless link  152 . MN  2   146  is coupled to a sector  1  base station  1  attachment point via wireless link  154 . MN  3   148  is coupled to a sector  1  base station  3  attachment point via wireless link  156 . MN  4   150  is coupled to a sector  3  base station  1  attachment point via wireless link  158 . MN  1   144  is, e.g., participating in a communications session with MN  2   146 . MN  3   148  is, e.g., participating in a communications session with MN  4   150 . 
     Exemplary wireless communications system  102  also includes a plurality of peer to peer wireless terminals (peer-peer wireless terminal  1   160 , peer-peer wireless terminal  2   162 , peer to peer wireless terminal  3   164 , peer to peer wireless terminal  4   166 ). In this example, peer-peer device  1   160  is communicating in a peer to peer communications session with peer-peer device  2   162  over wireless link  168 , and both peer to peer devices ( 160 ,  162 ) are located in sector  2   128  of cell  2   116 . In this example, peer-peer device  3   164  is communicating in a peer to peer communications session with peer-peer device  4   166  over wireless link  170 , and both peer to peer devices ( 164 ,  166 ) are located in sector  3   136  of cell  3   118 . 
     Table  106  identifies exemplary current wireless terminal frequency band usage. First column  182  identifies the wireless terminal and second column  184  identifies the corresponding frequency band usage. MN  1   144  currently uses frequency band f 2 . MN  2   146  currently uses frequency band f 1 . MN  3   148  currently uses frequency band f 1 . MN  4   150  currently uses frequency band f 3 . Peer to peer wireless terminal  1   160  and peer to peer wireless terminal  2   162  are currently using one of frequency band f 1  and frequency band f 3 . The selection of the frequency band, e.g., the selection of which one of f 1  band and f 3  band to use for peer to peer signaling, having been picked as a function of channel gain information with respect to the base stations. Peer to peer wireless terminal  3   164  and peer to peer wireless terminal  4   166  are currently using one of frequency band f 1  and frequency band f 2 . The selection of the frequency band, e.g., the selection of which one of f 1  band and f 2  band to use for peer to peer signaling, having been picked as a function of channel gain information with respect to the base stations. 
       FIG. 2  is a drawing  200  including a plurality of sectorized base stations ( 108 ,  110 ,  112 ) transmitting reference signals ( 204 ,  206 ,  208 ), respectively, and an exemplary peer to peer wireless terminal  202  which receives and measures those reference signals ( 204 ,  206 ,  208 ). In some embodiments, the reference signals ( 204 ,  206 ,  208 ) are one of base station beacon signals and base station pilot channel signals. The peer to peer wireless terminal  202  selects a frequency to use for peer to peer communications as a function of the signal measurements, e.g., selects the frequency band corresponding to the smallest channel gain. 
       FIG. 2  also includes a flowchart  250  of an exemplary method of operating a peer to peer communications device in accordance with various embodiments. Operation starts in step  252 , where the peer to peer communications device is powered on and initialized. Operation proceeds from step  252  to step  254 . In step  254  the peer to peer communications device measures the received power level of base station reference signals corresponding to different frequency bands. In some embodiments, step  254  includes sub-steps  256 ,  258  and  260 . In sub-step  256 , the peer to peer communications device measures the received power level of a reference signal from a first base station, e.g., a reference signal from base station  1   108 , corresponding to a first frequency, e.g., corresponding to frequency f 1 . For example, the signal measured in sub-step  256  is signal  204 . In sub-step  258 , the peer to peer communications device measures the received power level of a reference signal from a second base station, e.g., a reference signal from base station  2   110 , corresponding to a second frequency, e.g., corresponding to frequency f 2 . For example, the signal measured in sub-step  258  is signal  206 . In sub-step  260 , the peer to peer communications device measures the received power level of a reference signal from a third base station, e.g., a reference signal from base station  3   112 , corresponding to a third frequency, e.g., corresponding to frequency f 3 . For example, the signal measured in sub-step  260  is signal  208 . Operation proceeds from step  254  to step  262 . 
     In step  262 , the peer to peer wireless communications device selects a frequency to use as a function of the measured power level information. In some embodiments, step  262  includes sub-steps  264  and  266 . In sub-step  264 , the peer to peer communications device determines the smallest channel gain, e.g., determines which received base station reference signal strength is the lowest. Then, in sub-step  266  the peer to peer communications device determines the frequency corresponding to the smallest channel gain. For example, in the example of drawing  200  consider that the signal  208  is received at the lowest power level since peer to peer device  202  is furthest away from base station  112 . In such a case peer to peer communications device  202  selects frequency f 3  to use since frequency f 3  corresponds to signal  208 . 
     Operation proceeds from step  262  to step  268 . In step  268 , the peer to peer communications device communicates, e.g., transmits or receives, a peer to peer signal using the selected frequency from step  262 . 
       FIG. 3  includes a drawing  300  illustrating exemplary pairs of frequency bands in an exemplary FDD WAN communications system which also supports peer to peer signaling, and a table  350  illustrating exemplary peer to peer related information including exemplary selection criteria. Horizontal line  302  represents frequency which includes a frequency division duplex uplink  304  and a frequency division duplex downlink  306 . The FDD uplink  304  is partitioned to include (first portion  308 , second portion  310 , third portion  312 ) associated with (frequency f 1UL , frequency f 2UL , frequency f 3UL ), respectively. The FDD downlink  306  is partitioned to include (first portion  314 , second portion  316 , third portion  318 ) associated with (frequency f 1DL , frequency f 2DL , frequency f 3DL ), respectively. The uplink band  308  associated with f 1UL  and the downlink band  314  associated with f 1DL  form a 1 st  corresponding pair as indicated by arrow  320 . The uplink band  310  associated with f 2UL  and the downlink band  316  associated with f 2DL  form a  2   nd  corresponding pair as indicated by arrow  322 . The uplink band  312  associated with f 3UL  and the downlink band  318  associated with f 3DL  form a 2 rd  corresponding pair as indicated by arrow  324 . Table  350  includes a first column  352  which indicates the WAN frequency band used for peer to peer signaling, a second column  354  which indicates measured signals used by peer to peer wireless terminals for band selection, and a third column  356  which indicates exemplary selection criteria. 
     Row  358  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN uplink band, the measured signals used by a peer to peer wireless terminal for band selection are base station broadcast signals, e.g., base station beacon signals in the WAN downlink band. Row  358  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects an uplink band corresponding to the weakest received WAN base station broadcast signal, e.g., the weakest received base station beacon signal. For example, consider that a peer to peer wireless terminal monitors for and receives a broadcast signal, e.g., a beacon signal, from downlink bands ( 314 ,  316 ,  318 ). Continuing with the example, consider that a peer to peer wireless terminal determines that the weakest received signal is from the downlink band with frequency f 2DL    316 . Under this exemplary selection criteria, the peer to peer wireless terminal selects to use the uplink band associated with f 2UL    310  for peer to peer signaling communications. 
     Row  360  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN downlink band, the measured signals used by a peer to peer wireless terminal for band selection are WAN wireless terminal transmission signals, e.g., a WAN mobile node user beacon broadcast signal in the uplink band, a WAN mobile node dedicated control channel uplink signal in the uplink band or a WAN mobile node user reverse pilot signal in the uplink band. Row  360  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects a downlink band corresponding to the weakest received WAN WT transmission signal, e.g., the weakest received WAN mobile node user beacon broadcast signal in the uplink band, a WAN mobile node dedicated control channel uplink signal in the uplink band or a WAN mobile node user reverse pilot signal in the uplink band. For example, consider that a peer to peer wireless terminal monitors for and receives transmission signals from WAN WTs, e.g., WAN WT beacon signal, in uplink bands ( 308 ,  310 ,  312 ). The peer to peer WT identifies the strongest received WAN WT beacon signal corresponding to each of the bands ( 308 ,  310 ,  312 ). Then the peer to peer wireless terminal identifies which one of those signals is the weakest. Continuing with the example, consider that a peer to peer wireless terminal determines that the weakest received signal of the three strongest signals is from the uplink band with frequency f 3UL    312 . Under this exemplary selection criteria, the peer to peer wireless terminal selects to use the downlink band associated with f 3DL    318  for peer to peer signaling communications. 
       FIG. 4  includes a drawing  400  illustrating exemplary pairs of frequency bands in an exemplary FDD WAN communications system which also supports peer to peer signaling, and a table  450  illustrating exemplary peer to peer related information including exemplary selection criteria. Horizontal line  402  represents frequency which includes a frequency division duplex uplink  404  and a frequency division duplex downlink  406 . The FDD uplink  404  is partitioned to include (first portion  408 , second portion  410 , third portion  412 ) associated with (frequency f 1UL , frequency f 2UL , frequency f 3UL ), respectively. The FDD downlink  406  is partitioned to include (first portion  414 , second portion  416 , third portion  418 ) associated with (frequency f 1DL , frequency f 2DL , frequency f 3DL ), respectively. The uplink band  408  associated with f 1UL  and the downlink band  414  associated with f 1DL  form a 1 st  corresponding pair as indicated by arrow  420 . The uplink band  410  associated with f 2UL  and the downlink band  416  associated with f 2DL  form a 2 nd  corresponding pair as indicated by arrow  422 . The uplink band  412  associated with f 3UL  and the downlink band  418  associated with f 3DL  form a 3 rd  corresponding pair as indicated by arrow  424 . Table  450  includes a first column  452  which indicates the WAN frequency band used for peer to peer signaling, a second column  454  which indicates measurements used by peer to peer wireless terminals for band selection, and a third column  456  which indicates exemplary selection criteria. 
     Row  458  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN uplink band, the measurements used by a peer to peer wireless terminal for band selection are interference from WAN WTs in the uplink band. Row  458  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects an uplink band corresponding to the lowest level of interference. For example, consider that a peer to peer wireless terminal monitors for and receives uplink signals from WAN WTs in each of the uplink bands ( 408 ,  410 ,  412 ), the received WAN WT uplink signals representing interference from the perspective of the peer to peer wireless terminal which would like to use the same uplink band for peer to peer signaling. Continuing with the example, consider that a peer to peer wireless terminal determines that the lowest level of interference is from the upband with frequency f 1UL    408 , under this exemplary selection criteria, the peer to peer wireless terminal selects to use the uplink band associated with f 1UL    408  for peer to peer signaling communications. 
     Row  460  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN downlink band, the measurements used by a peer to peer wireless terminal for band selection are interference measurements from WAN base stations in the downlink band. Row  460  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects a downlink band corresponding to the lowest level of interference. For example, consider that a peer to peer wireless terminal monitors for and receives downlink signals from WAN base stations in each of the uplink bands ( 408 ,  410 , 412 ), the received WAN base station downlink signals representing interference from the perspective of the peer to peer wireless terminal which would like to use the same downlink band for peer to peer signaling. Continuing with the example, consider that a peer to peer wireless terminal determines that the lowest level of interference is from the downlink band with frequency f 2DL    416 . Under this exemplary selection criteria, the peer to peer wireless terminal selects to use the downlink band associated with f 2DL    416  for peer to peer signaling communications. 
     Note that the approach of the examples of  FIG. 3  favors the WAN communications devices, with the peer to peer band being selected to minimize impact to WAN signaling, e.g., minimize impact to wide area network signaling reception and recovery. Alternatively, the approach of the examples of  FIG. 4  favors the peer to peer communications devices, with the peer to peer band being selected to minimize impact to peer to peer signaling reception and recovery.  FIG. 5  illustrates exemplary embodiments incorporating features represented by both  FIG. 3  and  FIG. 4 . 
       FIG. 5  includes a drawing  500  illustrating exemplary pairs of frequency bands in an exemplary FDD WAN communications system which also supports peer to peer signaling, and a table  550  illustrating exemplary peer to peer related information including exemplary selection criteria. Horizontal line  502  represents frequency which includes a frequency division duplex uplink  504  and a frequency division duplex downlink  506 . The FDD uplink  504  is partitioned to include (first portion  508 , second portion  510 , third portion  512 ) associated with (frequency f 1UL , frequency f 2UL , frequency f 3UL ), respectively. The FDD downlink  506  is partitioned to include (first portion  514 , second portion  516 , third portion  518 ) associated with (frequency f 1DL , frequency f 2DL , frequency f 3DL ), respectively. The uplink band  508  associated with f 1UL  and the downlink band  514  associated with f 1DL  form a 1 st  corresponding pair as indicated by arrow  520 . The uplink band  510  associated with f 2UL  and the downlink band  516  associated with f 2DL  form a  2   nd  corresponding pair as indicated by arrow  522 . The uplink band  512  associated with f 3UL  and the downlink band  518  associated with f 3DL  form a 3 rd  corresponding pair as indicated by arrow  524 . Table  550  includes a first column  552  which indicates the WAN frequency band used for peer to peer signaling, a second column  554  which indicates measurements used by peer to peer wireless terminals for band selection, and a third column  556  which indicates exemplary selection criteria. 
     Row  558  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN uplink band, the measurements used by a peer to peer wireless terminal for band selection are: (i) measurements of base station broadcast signals, e.g., base station beacon signals in the WAN downlink band and (ii) measurements of interference from WAN WTs in the uplink. Row  558  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects an uplink band as a function of power measurements of received base station broadcast signals and interference measurements from the perspective of the peer to peer device corresponding to signals transmitted from WAN WTs. 
     Row  560  indicates that if the WAN frequency band being used for peer to peer signaling is a WAN downlink band, the measurements used by a peer to peer wireless terminal for band selection are: (i) measurements of WAN WT transmission signals, e.g., measurements of received WAN mobile node user beacon signal or measurements of received WAN mobile node dedicated control channel uplink signals, or measurements of received reverse link pilot channel signals, in the uplink and (ii) measurements of interference from WAN BSs in the downlink band. Row  560  further indicates that under such a scenario, in some embodiments, the peer to peer wireless terminal selects a downlink band as a function of power measurements or received transmission signals from WAN WTs and measurements of interference from WAN base stations from the perspective of the peer to peer wireless terminal, 
     In some embodiments, the relative weighting or impact to selection of a communications band using the selection criteria of column  556  changes as a function of at least one of the user of the peer to peer wireless terminal, a priority level, and a tier service level. For example, if the user of the peer to peer wireless terminal is an ordinary peer to peer user, the WAN wireless communications, in some embodiments, are favored and the impact to WAN signal reception has a high priority. For example, for uplink band selection a higher weighting is given to considerations of received power measurements from the base station broadcast signals than from interference being generated by WAN WT signaling. As another example, if the user of the peer to peer wireless terminal is a high priority user, e.g., an emergency services user, then a higher weighting is given to consideration of interference being experienced which impacts peer to peer communications than for interference being generated by the peer to peer device which affects WAN signaling communications. For example, for uplink band selection a higher weighting is given to measured interference from WAN WTs in the uplink band than to power measurements of received base station signaling. 
       FIG. 6  is a drawing  600  illustrating exemplary communications bands in a time division duplex system where different cells use different TDD duplex bands, and wherein at least some of air link resources are shared between WAN and peer to peer communications. Horizontal axis  602  indicates time. Block  604  indicates that exemplary cell  1  uses a first communications band identified by frequency f 1 . Block  606  indicates that exemplary cell  2  uses a second communications band identified by frequency f 2 . In this example bands  604  and  606  are non-overlapping. Corresponding to TDD frequency band  604  associated with frequency f 1  and cell  1  there are a sequence of uplink and downlink time slots (uplink slot  608 , downlink slot  610 , uplink slot  612 , downlink slot  614 , . . . ). Arrow  615  indicates that the same TDD frequency band  604  is used for both uplink and downlink for cell  1 , but corresponding to different times. Corresponding to TDD frequency band  606  associated with frequency f 2  and cell  2  there are a sequence of uplink and downlink time slots (uplink slot  616 , downlink slot  618 , uplink slot  620 , downlink slot  622 , . . . ). Arrow  624  indicates that the same TDD frequency band  606  is used for both uplink and downlink for cell  2 , but corresponding to different times 
       FIG. 7  is a drawing  700  illustrating exemplary communications bands in a time division duplex system where different cells using the same TDD bands but at different times, and wherein at least some of air link resources are shared between WAN and peer to peer communications. Horizontal axis  702  indicates time. Block  704  indicates a first communications band identified by frequency f 1 . Block  706  indicates a second communications band identified by frequency f 2 . In this example bands  604  and  606  are non-overlapping. For the frequency band  704  identified by frequency f 1 , there are a sequence of air link resources corresponding to different time slots (resource  708  for time slot T 1 , resource  710  for time slot T 2 , resource  712  for time slot T 3 , resource  714  for time slot T 4 ). This pattern repeats as indicated by the sequence of: resource  716  for time slot T 1 , resource  718  for time slot T 2 , resource  720  for time slot T 3 , resource  722  for time slot T 4 . For the frequency band  706  identified by frequency f 2 , there are a sequence of air link resources corresponding to different time slots (resource  728  for time slot T 1 , resource  730  for time slot T 2 , resource  732  for time slot T 3 , resource  734  for time slot T 4 ). This pattern repeats as indicated by the sequence of: resource  736  for time slot T 1 , resource  738  for time slot T 2 , resource  740  for time slot T 3 , resource  742  for time slot T 4 . 
     In this example slots designated T 1  and T 2  are used for the WAN uplink as indicated by arrow  748 , while slots designated T 3  and T 4  are used for the WAN downlink as indicated by arrow  750 . Arrow  752  identifies that time slot T 1  in combination with both frequency bands ( 704 ,  706 ) represents the cell  1  uplink WAN communications band. Arrow  754  identifies that time slot T 2  in combination with both frequency bands ( 704 ,  706 ) represents the cell  2  uplink WAN communications band. Arrow  756  identifies that time slot T 3  in combination with both frequency bands ( 704 ,  706 ) represents the cell  1  downlink WAN communications band. Arrow  758  identifies that time slot T 4  in combination with both frequency bands ( 704 ,  706 ) represents the cell  2  downlink WAN communications band. Arrow  724  indicates that both air link resource  708  and  712  form an uplink/downlink corresponding pair for cell  1  using TDD band  704 . Arrow  726  indicates that both air link resource  710  and  714  form an uplink/downlink corresponding pair for cell  2  using TDD band  704 . Arrow  744  indicates that both air link resource  728  and  732  form an uplink/downlink corresponding pair for cell  1  using TDD band  706 . Arrow  746  indicates that both air link resource  730  and  734  form an uplink/downlink corresponding pair for cell  2  using TDD band  706 . 
       FIG. 8  is a drawing  800  illustrating an exemplary frequency band in a TDD WAN system in which the same frequency band corresponds to multiple uplink/downlink bands, and wherein at least some of the air link resources are shared with peer to peer communications. Horizontal axis  802  represents time. The frequency band  804  associated with frequency f, corresponds to (air link resource  806  during time slot T 1 , air link resource  808  during time slot T 2 , air link resource  810  during time slot T 3 , air link resource  812  during time slot T 4 , air link resource  814  during time slot T 5 , air link resource  816  during time slot T 6 , air link resource  818  during time slot T 1 , air link resource  820  during time slot T 2 , air link resource  822  during time slot T 3 , air link resource  824  during time slot T 4 , air link resource  826  during time slot T 5 , air link resource  828  during time slot T 6 , . . . ). Uplink band  1  corresponds to TDD frequency band  804  during the time slots designated T 1  as indicated by designation indicator  830 . Downlink band  1  corresponds to TDD frequency band  804  during the time slots designated T 4  as indicated by designation indicator  832 . Uplink band  1  and downlink band  1  form a first corresponding set as indicated by arrow  834 . Uplink band  2  corresponds to TDD frequency band  804  during the time slots designated T 2  as indicated by designation indicator  836 . Downlink band  2  corresponds to TDD frequency band  804  during the time slots designated T 5  as indicated by designation indicator  838 . Uplink band  2  and downlink band  2  form a second corresponding set as indicated by arrow  840 . Uplink band  3  corresponds to TDD frequency band  804  during the time slots designated T 3  as indicated by designation indicator  842 . Downlink band  3  corresponds to TDD frequency band  844  during the time slots designated T 6  as indicated by designation indicator  844 . Uplink band  3  and downlink band  3  form a third corresponding set as indicated by arrow  846 . 
       FIG. 9  is a drawing of an exemplary communications system  900  supporting WAN signaling and peer to peer signaling in accordance with various embodiments. Exemplary communications system  900  includes a plurality of base stations (BS  1   902 , BS  2   904 , BS  3   906 , BS  4   908 , BS  5   910 , BS  6   912 ) coupled together and to other network nodes, e.g., other base stations, home agent nodes, system control nodes, AAA nodes, etc., and/or the Internet via backhaul network  914 . Exemplary communications system  900  also includes a plurality of WAN wireless terminals, e.g., mobile WAN WTs, (WAN WT  1   916 , WAN WT  2   920 ) and a plurality of peer to peer wireless terminals, e.g. mobile peer to peer WTs, (P-P WT  1   924 , P-P WT  2   926 ). WAN WT  1   916  is currently coupled to BS  1   902  via wireless link  918 , while WAN WT  2   920  is currently coupled to an attachment point of BS  6   912  via wireless link  922 . P-P wireless terminal  1   924  is communicating with P-P wireless terminal  2   926  via peer to peer communications link  928 . Received signaling from WAN devices, e.g., base station and/or WAN WTs, in some embodiments, affects operations of the peer to peer wireless terminals ( 924 ,  926 ), e.g., in regards to band selection to use for peer to peer signaling. Exemplary GPS satellites ( 930 ,  932 ) are also shown. In some embodiments, received GPS signals affect operation of the peer to peer wireless terminals ( 924 ,  926 ), e.g., with the peer to peer wireless terminals determining location from the received signal, and using location information to determine from stored mapping information a designated band to use for peer to peer signaling. The designated band may be, and sometime is a band which is shared between WAN signaling use and peer to peer signaling use. 
     Exemplary base station  1   902  is a single sector base station supporting an uplink WAN communications band and a downlink WAN communications band. Exemplary base station  2   904  is a single sector base station supporting multiple uplink/downlink WAN communications band pairs with the different downlink bands corresponding to the same or substantially the same power reference levels. Exemplary base station  3   906  is a single sector base station supporting multiple uplink/downlink WAN communications band pairs with the different downlink bands corresponding to different power reference levels. 
     Exemplary base station  4   908  is a multi-sector base station supporting an uplink communications band/downlink WAN communications band pair in at least two sectors. Exemplary base station  5   910  is a multi-sector sector base station supporting multiple uplink/downlink WAN communications band pairs in at least two sectors with different downlink bands corresponding to the same or substantially the same power reference levels. Exemplary base station  6   912  is a multi-sector base station supporting multiple uplink/downlink WAN communications band pairs in at least two sectors with the different downlink bands corresponding to different power reference levels. 
     In some embodiments, each of the base stations uses a WAN FDD implementation. In some embodiments, each of the base stations uses a WAN FDD implementation. In some embodiments, portions of the communications system use WAN FDD while other portions of the communications system use WAN TDD. 
     The peer to peer wireless terminals ( 924 ,  926 ) may implement some or all of the methods described in the flowcharts of  FIGS. 10 ,  11 ,  12 ,  13 ,  14 , and  15  or any of the other described methods, e.g., methods described with respect to  FIGS. 1 ,  2 ,  3 ,  4 ,  5 ,  6 , or  7 . The peer to peer wireless terminals ( 924 ,  926 ) may be any of the peer to peer wireless terminals of  FIG. 1 ,  2 ,  17 ,  18  or  19 . 
       FIG. 10  is a flowchart  1000  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1002 , where the communications device is powered on and initialized and proceeds to step  1004 . In step  1004 , the communications device receives a signal from a wide area network (WAN) communications device, said signal having been transmitted by the WAN device in one of a plurality of WAN communications bands. Operation proceeds from step  1004  to step  1006 . 
     In step  1006 , the communications device decodes the received signal to recover communicated information from said received signal. In some embodiments, the recovered communicated information indicates one of the plurality of communications bands which is one of: i) unused by a sector of the WAN device from which the signal was received and ii) used by the sector of the WAN device from which the signal was received but at reduced power level in said sector relative to the other ones of said plurality of WAN frequency bands. In some such embodiments, the WAN device is a multi-sector base station. In some other such embodiments, the WAN device is a single sector base station and said sector is the single sector of said single sector base station. 
     Then, in step  1008 , the communications device selects one of the WAN communications bands for peer to peer communications based on the received signal. Step  1008  includes sub-step  1010 . In sub-step  1010 , the communications device uses the recovered communicated information to select between said plurality of WAN communications bands. In some embodiments, selecting the WAN band indicates selecting the WAN communications band indicted by said information. In some embodiments, the selected communications band is different from the communications band from which the received signal was received. 
     Operation proceeds from step  1008  to step  1012 . In step  1012 , the communications device transmits a peer to peer signal in the selected one of the WAN communications bands. 
     In some embodiments, the plurality of WAN communications bands are frequency division duplex (FDD) bands, and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments the selected communications band is a WAN uplink communications band. 
     In some other embodiments, the plurality of WAN communications bands are time division duplex (TDD) communications bands, and the WAN communications band from which the signal is received is received in a time slot within a downlink communications band. In some such embodiments, the selected communications band is an uplink band and said peer to peer signal is communicated in an uplink time slot of said uplink communications band, the uplink and downlink communications bands using the same frequency but at different times. 
     In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one communications band is not used by a sector of at least one cell at any given time. In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein in at least one sector of a cell which uses multiple communications bands at the same time, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. In some embodiments, the device from which the WAN is received is a WAN communications device which uses only a subset of said WAN communications bands, said subset including less than the full plurality of WAN communications bands. 
       FIG. 11  is a flowchart  1100  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1102 , where the communications device is powered on and initialized and proceeds to step  1104 . 
     In step  1104 , the communications device receives a signal from a wide area network (WAN) communications device, said signal having been transmitted by the WAN device in one of a plurality of WAN communications bands. Operation proceeds from step  1104  to step  1106 . In step  1106 , the communications device measures the signal strength of the received signal. 
     Then, in step  1008 , the communications device selects one of the WAN communications bands for peer to peer communications based on the received signal. Step  1108  includes sub-step  1010 . In sub-step  1010 , the communications device performs said selection as a function of the measured signal strength. Sub-step  1110  includes sub-step  1112  and  1114 . In sub-step  1112 , the communications device compares the measured signal strength to a threshold. Operation proceeds from sub-step  1112  to sub-step  1114 . In sub-step  1114 , the communications device selects a communications band corresponding to the band from which the said signal was received when said signal strength is below said threshold, said communications band corresponding to the band from which the signal was received, but being a different communications band from the band from which the signal was received. In some embodiments, the received signal is from a WAN base station and the communications band from which the signal is received is a downlink communications band, and the selected communications band is an uplink communications band corresponding to said downlink communications band. 
     Operation proceeds from step  1108  to step  1116 . In step  1116 , the communications device transmits a peer to peer signal in the selected one of the WAN communications bands. 
     In some such embodiments, the WAN device is a multi-sector base station. In some other such embodiments, the WAN device is a single sector base station. 
     In some embodiments, the plurality of WAN communications bands are frequency division duplex (FDD) bands, and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments the selected communications band is a WAN uplink communications band. 
     In some other embodiments, the plurality of WAN communications bands are time division duplex (TDD) communications bands, and the WAN communications band from which the signal is received is received in a time slot within a downlink communications band. In some such embodiments, the selected communications band is an uplink band and said peer to peer signal is communicated in an uplink time slot of said uplink communications band, the uplink and downlink communications bands using the same frequency but at different times. 
     In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one communications band is not used by a sector of at least one cell at any given time. In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein in at least one sector of a cell which uses multiple communications bands at the same time, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. In some embodiments, the device from which the WAN is received is a WAN communications device which uses only a subset of said WAN communications bands, said subset including less than the full plurality of WAN communications bands. 
       FIG. 12  is a flowchart  1200  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1202 , where the communications device is powered on and initialized and proceeds to step  1204 . 
     In step  1204 , the communications device receives a signal from a wide area network (WAN) communications device, said signal having been transmitted by the WAN device in one of a plurality of WAN communications bands. Operation proceeds from step  1204  to step  1206 . In step  1206 , the communications device measures the signal strength of the received signal. 
     Then, in step  1208 , the communications device selects one of the WAN communications bands for peer to peer communications based on the received signal. Step  1208  includes sub-step  1210 . In sub-step  1210 , the communications device performs said selection as a function of the measured signal strength. Sub-step  1210  includes sub-steps  1212  and  1214 . In sub-step  1212 , the communications device compares the measured signal strength to a threshold. Operation proceeds from sub-step  1212  to sub-step  1214 . In sub-step  1214 , the communications device selects a communications band from the plurality of WAN communications bands which does not correspond to the band from which the signal was received when the signal strength is above said threshold. 
     Operation proceeds from step  1208  to step  1216 . In step  1216 , the communications device transmits a peer to peer signal in the selected one of the WAN communications bands. 
     In some such embodiments, the WAN device is a multi-sector base station. In some other such embodiments, the WAN device is a single sector base station. 
     In some embodiments, the plurality of WAN communications bands are frequency division duplex (FDD) bands, and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments the selected communications band is a WAN uplink communications band. 
     In some other embodiments, the plurality of WAN communications bands are time division duplex (TDD) communications bands, and the WAN communications band from which the signal is received is received in a time slot within a downlink communications band. In some such embodiments, the selected communications band is an uplink band and said peer to peer signal is communicated in an uplink time slot of said uplink communications band, the uplink and downlink communications bands using the same frequency but at different times. 
     In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one communications band is not used by a sector of at least one cell at any given time. In some embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein in at least one sector of a cell which uses multiple communications bands at the same time, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. In some embodiments, the device from which the WAN is received is a WAN communications device which uses only a subset of said WAN communications bands, said subset including less than the full plurality of WAN communications bands. 
       FIG. 13  is a flowchart  1300  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1302 , where the communications device is powered on and initialized and proceeds to step  1304 . 
     In step  1304 , the communications device receives signals from different wide area network communications bands. Step  1304  includes sub-steps  1306  and  1308 . In some embodiments, step  1304 , includes, during some times, sub-step  13   10 . 
     In sub-step  1306 , the communications device receives a signal from a wide area network (WAN) communications device, said signal having been transmitted by the WAN device in a first one of said plurality of WAN communications bands. In sub-step  1308 , the communications device receives a second signal from a wide area network (WAN) communications device, said second signal having been transmitted in a second one of said plurality of WAN communications bands, said first and second bands being different. In sub-step  1310 , the communications device receives a third signal from a wide area network (WAN) communications device, said third signal having been transmitted in a third one of said plurality of WAN communications bands, said third band being different from said first and second communications bands. The same WAN device may have transmitted said first and second received signals. Alternatively, different WAN devices may have transmitted said first and second received signals. The same WAN device may have transmitted said third and at least one of said first and second received signals. A different WAN device may have transmitted said received third signal than transmitted said received first signal. A different WAN device may have transmitted said received third signal than transmitted said received second signal. 
     Operation proceeds from step  1304  to step  1312 . In step  1312 , the communications device measures the received signal strength of WAN communications signals received from different WAN communications bands. Operation proceeds from step  1312  to step  1314 . In step  1314 , the communications device selects one of the WAN communications bands for peer to peer communications based on the received signal. Step  1314  includes sub-step  1315 . In sub-step  1315 , the communications device selects the communications band as a function of the measured signal strength of at least two different received signals. In some embodiments, sub-step  1315  includes sub-step  1316 . In sub-step  1316 , the communications device selects the communications band which corresponds to the band from which the weakest one of said measured received WAN signals was received. Operation proceeds from step  1314  to step  1318 . In step  1318 , the communications device transmits a peer to peer signal in the selected one of the WAN communications bands. 
     In some such embodiments, one or more of the WAN devices are multi-sector base stations. In some embodiments, one or more of the WAN devices are single sector base stations. 
     In some embodiments, the plurality of WAN communications bands are frequency division duplex (FDD) bands, and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments the selected communications band is a WAN uplink communications band. 
     In some other embodiments, the plurality of WAN communications bands are time division duplex (TDD) communications bands, and the WAN communications band from which the signal is received is received in a time slot within a downlink communications band. In some such embodiments, the selected communications band is an uplink band and said peer to peer signal is communicated in an uplink time slot of said uplink communications band, the uplink and downlink communications bands using the same frequency but at different times. 
     In some embodiments, a device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one communications band is not used by a sector of at least one cell at any given time. In some embodiments, a device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein in at least one sector of a cell which uses multiple communications bands at the same time, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. In some embodiments, a device from which the WAN is received is a WAN communications device which uses only a subset of said WAN communications bands, said subset including less than the full plurality of WAN communications bands. 
       FIG. 14  is a flowchart  1400  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1402 , where the communications device is powered on and initialized and proceeds to step  1404 . 
     In step  1404 , the communications device receives signals from different wide area network communications bands. Step  1404  includes sub-steps  1406  and  1408 . In some embodiments, step  1404  includes, during some times, sub-step  1410 . 
     In sub-step  1406 , the communications device receives a signal from a wide area network (WAN) communications device, said signal having been transmitted by the WAN device in a first one of said plurality of WAN communications bands. In sub-step  1408 , the communications device receives a second signal from a wide area network (WAN) communications device, said second signal having been transmitted in a second one of said plurality of WAN communications bands, said first and second bands being different. In sub-step  1410 , the communications device receives a third signal from a wide area network (WAN) communications device, said third signal having been transmitted in a third one of said plurality of WAN communications bands, said third band being different from said first and second communications bands. The same WAN device may have transmitted said first and second received signals. Alternatively, different WAN devices may have transmitted said first and second received signals. The same WAN device may have transmitted said third and at least one of said first and second received signals. A different WAN device may have transmitted said received third signal than transmitted said received first signal. A different WAN device may have transmitted said received third signal, then transmitted said received second signal. 
     Operation proceeds from step  1404  to step  1412 . In step  1412 , the communications device measures the received signal strength of WAN communications signals received from different WAN communications bands. Operation proceeds from step  1412  to step  1413 , in which the communications devices receives peer to peer signals. Then, in step  1414 , the communications device measures peer to peer signals from communications bands corresponding to the communications bands from which at least some of said measured WAN communications signals were received. For example, in some embodiments, if the WAN devices from which signals are received are base stations and the received WAN signals are downlink signals communicated in downlink bands, the received peer to peer signals are from peer to peer communications devices using uplink bands, said uplink bands being corresponding bands with respect to said downlink bands. As another example, in some embodiments, if the WAN devices from which signals are received are mobile nodes operating a cellular mode and the received WAN signals are uplink signals communicated in uplink bands, the received peer to peer signals are from peer to peer communications devices using uplink downlink, said downlink bands being corresponding bands with respect to said uplink bands. 
     Operation proceeds from step  1414  to step  1416 . In step  1416 , the communications device selects one of the WAN communications bands for peer to peer communications based on the received signal. Step  1416  includes sub-step  1418 . In sub-step  1418 , the communications device selects the communications band as a function of the measured signal strength of said received WAN signals and the measured signal strength of at least some peer to peer signals. Operation proceeds from step  1416  to step  1420 . In step  1420 , the communications device transmits a peer to peer signal in the selected one of the WAN communications bands. 
     In some such embodiments, one or more of the WAN devices are multi-sector base stations. In some embodiments, one or more of the WAN devices are single sector base stations. 
     In some embodiments, the plurality of WAN communications bands are frequency division duplex (FDD) bands, and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments the selected communications band is a WAN uplink communications band. 
     In some other embodiments, the plurality of WAN communications bands are time division duplex (TDD) communications bands, and the WAN communications band from which the signal is received is received in a time slot within a downlink communications band. In some such embodiments, the selected communications band is an uplink band and said peer to peer signal is communicated in an uplink time slot of said uplink communications band, the uplink and downlink communications bands using the same frequency but at different times. 
     In some embodiments, a device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one communications band is not used by a sector of at least one cell at any given time. In some embodiments, a device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein in at least one sector of a cell which uses multiple communications bands at the same time, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. In some embodiments, a device from which the WAN is received is a WAN communications device which uses only a subset of said WAN communications bands, said subset including less than the full plurality of WAN communications bands. 
       FIG. 15  is a flowchart  1500  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. For example, this exemplary method is used in some wireless communications systems including a plurality of wide area network communications bands, wherein at least some of the plurality of communications bands are not utilized by at least some base station sectors for cellular communications during at least some time periods. Operation starts in step  1502 , where the communications device is powered on and initialized and proceeds to step  1504 . In step  1504 , the communications device monitors to receive a signal in a first communications band. Operation proceeds from step  1504  to step  1506 . 
     In step  1506 , the communications device determines if a signal having a signal power level over a threshold level was received in a predetermined period of time from said first communications band. If a signal having a signal power level over the threshold level was received operation proceeds from step  1506  to step  1508 ; otherwise operation proceeds from step  1506  to step  1510 , in which the communications device selects a corresponding communications band which corresponds to said first communications band for use in communicating peer to peer signals. 
     Returning to step  1508 , in step  1508 , the communications device monitors to receive a signal in a second communications band. Operation proceeds from step  1508  to step  1512 . 
     In step  1512 , the communications device determines if a signal having a signal power level over a threshold level was received in a predetermined period of time from said second communications band. If a signal having a signal power level over the threshold level was received operation proceeds from step  1512  to step  1514 ; otherwise operation proceeds from step  1512  to step  1516 , in which the communications device selects a corresponding communications band which corresponds to said second communications band for use in communicating peer to peer signals. 
     Returning to step  1514 , in step  1514 , the communications device monitors to receive a signal in a third communications band. Operation proceeds from step  1514  to step  1518 . 
     In step  1518 , the communications device determines if a signal having a signal power level over a threshold level was received in a predetermined period of time from said third communications band. If a signal having a signal power level over the threshold level was received operation proceeds from step  1518  to step  1522 ; otherwise operation proceeds from step  1518  to step  1520 , in which the communications device selects a corresponding communications band which corresponds to said third communications band for use in communicating peer to peer signals. 
     Returning to step  1522 , in step  1522  the communications device selects a corresponding communications band which corresponds to one of said first, second and third communications bands for use in communication of peer to peer signals. In some embodiments, the selection of step  1522  is performed as a function of signal power level information. For example, the communications device determines which one of said signals received from the first, second and third communications bands was received at the lowest power level and selects the peer to peer communications band as the band which corresponds to the band in which the lowest power level signal was received. 
     Operation proceeds from any of step  1510 ,  1516 ,  1520 , and  1522  to step  1524 . In step  1524 , the communications device transmits a peer to peer communications signal in said selected corresponding communications band. 
     In some embodiments, a corresponding communications band is the same as a communications band. For example, lack of detected signal in a monitored communications band may, and sometimes does, indicate that the same communications band is available for peer to peer signaling usage. 
     In some embodiments, a corresponding communications band is different from a monitored communications band. For example, in some embodiments communications bands are paired, with one communications band being monitored for signals and with the corresponding band of the pair being conditionally available for peer to peer signaling. In some such embodiments, a communications band is a WAN downlink band in a frequency division duplex system and the corresponding frequency band is an uplink frequency band in said frequency division duplex system. For example, (first, second, and third) monitored communications bands are, in some embodiments, (first, second, and third) downlink communications bands which are non-overlapping. The (first, second, and third) downlink communications bands have (first, second, and third) corresponding uplink communications bands, respectively, which are non-overlapping, and the communications device selects one of said first, second, and third uplink communications bands for peer to peer signaling. 
     In some embodiments, a communications band is a WAN downlink band in a TDD system and a corresponding communications band is an uplink band in the TDD system. 
     Although the example of  FIG. 15  has been illustrated for the case of three bands which are monitored, in other embodiments, a different number of bands are monitored. In some embodiments, only one band is monitored, and the wireless communications device is allowed to use its corresponding band for peer to peer signaling if no received signal having a power level above a threshold is received in a predetermined period of time. In some other embodiments, two bands or more than three bands are monitored, and the communications device determines which corresponding band to use as a function of power level information. 
       FIG. 16  is a flowchart  1600  of an exemplary method of operating a communications device supporting peer to peer communications in accordance with various embodiments. Operation starts in step  1602 , where the communications device is powered on and initialized and proceeds to step  1604 , where the communications device receives a signal. In some embodiments, the received signal is a GPS signal. In some embodiments, the received signal is a user input signal received from a user input device included in said communications device. For example, the user input device is a keypad on the communications device and the user input signal indicates that the user has entered a particular address, e.g., intersection of two streets or a building address or a set of location information such as GPS coordinates or grid system coordinates. In some embodiments, the received signal is from an external device coupled to said communications device, e.g., the received signal is from a navigation device such as a vehicle navigation system or handheld navigation system coupled to said communications device. Then, in step  1606 , the communications device determines from the received signal a current location of the communications device. 
     In some embodiments, the received signal is a cellular network signal. For example, the cellular network, in some embodiments, tracks location of communications devices using a plurality of location techniques including, e.g., GPS information, network attachment point information identifying base station and/or sector, historical information, power information, relative power information, dead spot information, reception information and/or interference information, and device estimated position information can be uploaded. 
     Operation proceeds from step  1606  to step  1608 . In step  1608 , the communications device uses the determined location information to determine a communications band to be used for communications with other devices. The determined communications band is, e.g., a peer to peer communications band. In some embodiments, different communications bands are determined for peer to peer and WAN communications at the determined current location. 
     In some embodiments using the determined location information includes performing a lookup operation in which the current location of the communications device is used to identify a communications band associated with the current location in a stored set of information. In various embodiments, the stored set of information includes information indicating communications bands to be used for peer to peer communications at a plurality of different locations. In some embodiments, the communications device further supports wide area network communications and the set of stored information further includes information indicating communications bands to be used for wide area network communications at a plurality of different locations. 
     In some embodiments, the stored set of information indicates different frequency bands to be used for peer to peer and wide area network communications at one location. In some embodiments, the stored set of information indicates information that indicates that the same frequency bands are to be used for peer to peer and wide area network communications at one location. In some embodiments, the stored set of information is stored in said communications device. 
     In some embodiments, using the determined location information includes: sending a query to a network device; and receiving from said network device an indication of the communications band associated with the current location. In some embodiments, the received indication of the communications band indicates a communications band identified by information included in a stored set of information accessed by the network device, said stored set of information including information indicating communications bands to be used for peer to peer communications at a plurality of different locations. In some such embodiments, the communications device further supports wide area network communications and the set of stored information further includes information indicating communications bands to be used for wide area network communications at a plurality of different locations. 
     In some embodiments, the stored set of information indicates different frequency bands to be used for peer to peer and wide area network communications at one location. In some embodiments, the stored set of information indicates information that indicates that the same frequency band is to be used for peer to peer and wide area network communications at one location. Thus in some embodiments, different frequency bands at a location may be and sometimes are classified into different usage categories, e.g., for WAN signaling exclusively, for peer to peer signaling exclusively, for both peer to peer and WAN signaling to be used concurrently, e.g., with each type of signaling acting as interference to the other type. 
     The approach of maintaining, updating and using stored information correlating band usage types information, e.g., information designating bands to be available for peer to peer communications, with location information is beneficial in various embodiments implementing dynamic communications band allocation and/or reallocation, e.g., by a base station, as a function of current and/or estimated cellular and/or peer to peer activities in a region. This approach, including updating a set of location/band association information stored in the wireless terminal, e.g., via network node signaling, is also useful in phased deployment implementations, where the spectrum availability and/or base station capabilities vary over time. 
     Operation proceeds from step  1608  to step  1610 . In step  1610 , the communications device transmits a peer to peer signal in the determined communications band. 
       FIG. 17  is a drawing of an exemplary wireless terminal  1700 , e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments. Exemplary wireless terminal  1700  includes a receiver module  1702 , a transmitter module  1704 , a processor  1706 , user I/O devices  1708 , and a memory  1710  coupled together via a bus  1712  over which the various elements may exchange data and information. 
     Receiver module  1702 , e.g., an OFDM or CDMA wireless receiver, is coupled to receive antenna  1714  via which the wireless terminal  1700  receives signals. Received signals include signals from WAN devices, e.g., a downlink signal from a base station used for peer to peer band selection purposes. Receiver module  1702  receives a signal from a WAN communications device, the signal having been transmitted by the WAN device in one of a plurality of WAN communications bands. Received WAN signals ( 1734 , . . . ,  1736 ) represent such signals. Received signals received by module  1702  also include signals from other peer to peer devices. In some embodiments, received peer to peer signals are also utilized in selecting a peer to peer communications band. Received peer to peer signals also include received peer to peer signals as part of an ongoing peer to peer communications session. 
     Transmitter module  1704 , e.g., an OFDM or CDMA wireless transmitter, is coupled to transmit antenna  1716  via which the wireless terminal  1700  transmits signals, e.g., peer to peer signals to other wireless terminals operating in a peer to peer communications mode of operation. Transmitter module  1704  transmits a peer to peer signal in the selected one of the WAN communications bands which the wireless terminal uses for peer to peer signaling, e.g., the WAN communication band identified by information  1748 . In some embodiments, the same antenna is used for both transmitter and receiver. In some embodiments multiple antenna are used for at least one of reception and transmission, e.g., as part of a MIMO configuration. 
     User I/O devices  1708  include, e.g., microphone, keyboard, keypad, switches, camera, speaker, display, etc. User I/O devices  1708  allow a user of wireless terminal  1700  to input data/information, access output data/information, and control at least some function of the wireless terminal, e.g., initiate a peer to peer communications session. 
     Memory  1710  includes routines  1718  and data/information  1720 . The processor  1706 , e.g., a CPU, executes the routines  1718  and uses the data/information  1720  in memory  1710  to control the operation of the wireless terminal  1700  and implement methods, e.g., a method of one of: flowchart  1000  of  FIG. 10 , flowchart  1100  of  FIG. 11 , flowchart  1200  of  FIG. 12 , flowchart  1300  of  FIG. 13 , and flowchart  1400  of  FIG. 14 . 
     Routines  1718  include a peer to peer communications band selection module  1722 . Routines  1718  include one or more of decoder module  1724 , signal strength measurement module  1726 , weakest WAN band determination module  1728  and peer to peer signal strength measurement module  1732 . 
     Data/information  1720  includes a plurality of received WAN signals (received WAN signal  1   1734 , . . . , received WAN signal n  1736 ), stored communications band structure information  1746 , and information identifying a selected WAN band for peer to peer signaling  1748 . In some embodiments data/information  1720  includes one of more of the following: recovered information from WAN signals (recovered information from WAN signal  1   1738 , . . . , recovered information from WAN signal n  1740 ), measured signal strength information corresponding to received WAN signals (measured signal strength information for WAN signal  1   1742 , . . . , measured signal strength information for WAN signal n  1744 ), and band selection signal strength threshold information  1750 . 
     Stored communications band structure information  1746  includes one or more of: frequency division duplex (FDD) air link resource structure information  1752  and time division duplex (TDD) air link resource structure information  1754 . FDD air link resource structure information  1752  includes information corresponding to a plurality of corresponding uplink/downlink band pairs ((uplink band  1  information  1756 , downlink band  1  information  1758 ), . . . (uplink band N information  1760 , downlink band N information  1762 ). TDD air link resource structure information  1754  includes information corresponding to a plurality of corresponding uplink/downlink band pairs (uplink band  1  information  1764 , downlink band  1  information  1766 ), . . . (uplink band M information  1768 , downlink band M information  1770 ). Uplink band  1  information  1764  includes frequency information  1772  and time slot information  1774 . Downlink band  1  information  1766  includes frequency information  1776  and time slot information  1778 . In some embodiments, the frequency information  1772  is the same as frequency information  1776 . 
     Peer to peer communications band selection module  1722  selects one of a plurality of WAN communications bands based on a received WAN signal. Selected WAN band for peer to peer  1748  identifies the selection of selection module  1722 , and is used by wireless terminal  1700  for subsequent peer to peer communications, e.g., for tuning and/or controlling operation of the receiver module  1702  and transmitter module  1704  to support peer to peer signaling. 
     Decoder module  1724  decodes, prior to selecting one of the WAN frequency bands, a received signal to recover communicated information from the received signal. For example, decoder module  1724  decodes one or more of received WAN signals ( 1734 , . . . ,  1736 ) to obtain recovered communicated information (recovered information from WAN signal  1   1738 , . . . , recovered information from WAN signal n  1740 ). In some such embodiments, the selection module  1722  uses the recovered communicated information to select between a plurality of WAN communications bands. In some such embodiments, the recovered communicated information indicates one of the plurality of frequency bands which is one of i) unused by a sector of the WAN device from which the signal is received and ii) used by the sector of the WAN device from which the signal was received but at a reduced power level in that sector relative to other ones of said plurality of WAN frequency bands. In some embodiments, the WAN device is a single sector base station and the sector is the single sector of the single sector base station. 
     In some embodiments, the selecting by selection module  1722  includes selecting the WAN communications band indicated by the recovered communicated information. 
     In some embodiments, the selected communications band selected by the selection module  1722  is different from the band from which the received signal was received. In some exemplary embodiments, the WAN communications bands are FDD communications bands and the communications band from which the WAN signal is received is a WAN downlink communications band. In some such embodiments, the selected communications band to use for peer to peer communications is a WAN uplink communications band. 
     In some embodiments, the WAN communications bands are TDD communications bands and the WAN communications band from which the WAN signal is received corresponds to a time slot within a downlink communications band. In some such embodiments, the selected communications band, selected by module  1722  to be used for peer to peer communications, is an uplink band and the transmitter module  1704  transmits a generated peer to peer signal in an uplink time slot within said uplink band, the uplink and downlink communications bands using the same frequency but at different times. 
     Signal strength measurement module  1726  measures the strength of received signals, e.g., the strength of one of more received WAN signals ( 1734 , . . . ,  1736 ). Measured signal strength information (measured signal strength for WAN signal  1   1742 , . . . , measured signal strength for WAN signal n  1744 ) represent outputs of signal strength measurement module  1726  derived from (received WAN signal  1   1734 , . . . , received WAN signal n  1736 ). In some such embodiments, the selection module  1722  performs the selection as a function of measured signal strength information. 
     In some embodiments, the peer to peer communications band selection module  1722  includes a signal strength threshold comparison module  1730 . Signal strength threshold comparison module  1730  uses the data/information  1720  including band selection signal strength threshold information  1750  to compare a measured signal strength to a threshold. In some such embodiments, the selection module  1722  selects a communications band corresponding to the band from which the signal was received when the signal strength is below the threshold, said communications band from which the signal was received being a different communications band from which the signal was received. For example, consider that the received WAN signal  1   1734  was received in a first downlink communications band, that the measured power of received WAN signal  1   1742  was determined to be below a threshold stored in threshold information  1750 , and that the first downlink communications band is paired with a first uplink communications band identified in the stored communications band structure information. In one such embodiment, the selection module  1722  selects the first uplink communications band to use for peer to peer communications. 
     In various embodiments, the signal strength measurement module  1726  is for measuring received signal strengths of WAN communications signals received from different WAN communications bands, and the selection module  1722  selects the communications band as a function of the measured signal strength of at least two different received signals. 
     Weakest WAN band determination module  1728  determines the WAN band having the weakest one of the measured received WAN signals. In some such embodiments, the selection module  1722  selects the communications band corresponding to the band from which the weakest one of the measured received WAN signals was received. In one exemplary embodiment, the received WAN signals are base station signals from communications downlink bands which are paired with uplink communications bands, and the selection module  1722  selects the uplink communications band which is paired with the downlink communications band from which the weakest received signal was received, to be used for peer to peer communications. In some embodiments, the base stations transmit the same type of WAN signal, e.g., a beacon or pilot channel signal, at the same power level which is detected, measured for receive signal strength, and evaluated with other similar signals to determine the weakest received one. 
     In some other embodiments, different base stations may, and sometimes do, transmit a WAN to be received, measured, and compared with WAN signals from other base stations at different transmission power levels. Scaling information, known to or supplied to, the wireless terminal  1700  is used by the wireless terminal  1700  to scale measurements of received WAN signals before performing a weakness determination by module  1728 . In some embodiments, adjustments are also made to take into account different SNR requirements at a WAN device which will be impacted by the peer to peer signaling. 
     Peer to peer signal measurement module  1732  measures peer to peer signals received from communications bands corresponding to the communications bands from which at least some of the measured WAN communications signals were received. In some such embodiments, the selection module  1722  selects a corresponding communications band as a function of the measured signal strength of received WAN signals and the measured signal strength of at least some peer to peer signals. 
     In some embodiments, the signal strength threshold comparison  1730  compares the measured signal strength to a threshold, and the selection module  1722  selects a communications band which does not correspond to the band from which the signal was received when the signal strength is above the threshold. For example, signal strength of a measured WAN base station downlink signal above a certain threshold, in some embodiments, indicates that the peer to peer device is too close to the base station, and allowing peer to peer communications in its corresponding uplink band would unacceptably impact WAN uplink signal recovery by the base station in that uplink band, and therefore peer to peer signaling in that uplink band is restricted. In some embodiments, the signal strength threshold comparison module  1730  is a separate module form selection module  1722 . 
     Stored communications band structure information  1746  indicates a correspondence between uplink and downlink communications bands. In some such embodiments, the receiver module  1702  receives a signal from a WAN base station and the communications band from which the signal is received is a downlink communications band, and the selection module  1722  uses the stored communications band structure information  1746  to select the uplink band corresponding to the downlink communications band to be used as the selected communications band for peer to peer communications. For example, consider that the communications system is a FDD system, that the received WAN signal ( 1734 ) is received in the downlink band identified by DL band  1  information  1758  and that the selected communications band selected by selection module  1722  to be used for peer to peer communications is the paired uplink band  1  identified by information  1756 . As another example, consider that the communications system is a TDD system, and that the received WAN signal ( 1734 ) is received in the downlink communications band identified by DL band  1  information  1766 , and that the selected communications band selection by selection module  1722  to be used for peer to peer communications is uplink band  1  identified by information  1764 . 
     In various embodiments, the device from which the WAN signal, e.g., signal  1734 , is received is a WAN communications device in a frequency division duplex multi-cell communications system wherein at least one band is not used by a sector of at least one cell at any given time. In some such embodiments, the unused band is available for use for peer to peer communications. Information identifying an unused WAN band available for peer to peer communications is, e.g., extracted from recovered information from WAN signal  1   1738 . In some embodiments, in different portions of the system different bands may be unused. In some embodiments, corresponding to the same base station attachment point, a WAN band is designated by the base station for one of: WAN exclusive use, WAN/peer to peer sharing, peer to peer exclusive use. In some embodiments, the designation changes over time, e.g., as a function of system loading. Designation information is, in some embodiments obtained in recovered information from a WAN signal. 
     In various embodiments, the device from which the WAN signal is received is a WAN communications device in a frequency division duplex multi-cell communication system in which at least one sector of a cell uses multiple communications bands at the same time. In some such embodiments, one of the communications bands is used at a reduced power level relative to another one of the communications bands used in said sector. For example, the sector includes three different downlink/uplink frequency band pairs, each pair associated with a different base station reference power level for downlink signaling. 
     In some embodiments, the device from which the WAN signal, e.g., received WAN  1  signal  1734 , is received is a WAN communications device, e.g., a base station, which uses only a subset of the WAN communications bands in the overall system, the subset including less than the full plurality of WAN communications bands. 
     In some embodiments, the wireless terminals supports peer to peer communications in both FDD WAN systems and TDD WAN systems, e.g., in one region or range of spectrum, the WAN system in use is a FDD system while in another region or range of spectrum the WAN system in use is a TDD WAN system. In some such embodiments, the wireless terminal  1700  supporting peer to peer communications adapts to accommodate the type of WAN system available. 
       FIG. 18  is a drawing of an exemplary wireless terminal  1800 , e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments. Exemplary wireless terminal  1800  includes a receiver module  1802 , a transmitter module  1804 , a processor  1806 , user I/O devices  1808 , and a memory  1810  coupled together via a bus  1812  over which the various elements may exchange data and information. 
     Receiver module  1802 , e.g., an OFDM or CDMA wireless receiver, is coupled to receive antenna  1814  via which the wireless terminal  1800  receives signals. Receiver module  1802  receives signals from at least one WAN communications band. Received signals include signals from WAN devices, e.g., a downlink signal from a base station used for peer to peer band selection purposes. Receiver module  1802  receives a signal from a WAN communications device, the signal having been transmitted by the WAN device in one of a plurality of WAN communications bands. Received WAN signals ( 1834 , . . . ,  1836 ) represent such signals. Received signals received by module  1802  also include signals from other peer to peer devices. In some embodiments, received peer to peer signals are also utilized in selecting a peer to peer communications band. Received peer to peer signals also include received peer to peer signals as part of an ongoing peer to peer communications session. 
     Transmitter module  1804 , e.g., an OFDM or CDMA wireless transmitter, is coupled to transmit antenna  1816  via which the wireless terminal  1800  transmits signals, e.g., generated peer to peer signals such as signal  1846  to other wireless terminals operating in a peer to peer communications mode of operation. Transmitter module  1804  transmits a peer to peer signal in the selected one of the WAN communications bands which the wireless terminal uses for peer to peer signaling, e.g., the WAN communication band identified by information  1844 . In some embodiments, the same antenna is used for both transmitter and receiver. In some embodiments multiple antenna are used for at least one of reception and transmission, e.g., as part of a MIMO configuration. 
     User I/O devices  1808  include, e.g., microphone, keyboard, keypad, switches, camera, speaker, display, etc. User I/O devices  1808  allow a user of wireless terminal  1800  to input data/information, access output data/information, and control at least some function of the wireless terminal, e.g., initiate a peer to peer communications session. 
     Memory  1810  includes routines  1818  and data/information  1820 . The processor  1806 , e.g., a CPU, executes the routines  1818  and uses the data/information  1820  in memory  1810  to control the operation of the wireless terminal  1800  and implement methods, e.g., the method of flowchart  1500  of  FIG. 15 . 
     Routines  1818  include a threshold determination module  1822 , a peer to peer communications band selection module  1830  and a peer to peer signal generation module  1832 . Threshold determination module  1822  includes a band monitoring module  1824 , a signal strength measurement module  1826  and a threshold test module  1828 . 
     Data/information  1820  includes one or more received WAN signals (received WAN signal  1   1834 , . . . , received WAN signal n  1836 ), measured signal strength information (measured signal strength for WAN signal  1   1838 , . . . , measured signal strength for WAN signal n  1840 ), band selection threshold information  1842 , stored correlation information between monitored bands and peer to peer usage bands  1843 , stored communications band structure information  1848 , information identifying a selected corresponding communications band for peer to peer signaling  1844 , and a generated peer to peer signal  1846 . 
     Stored communications band structure information  1848  includes one or more of FDD air link resource structure information  1850  and TDD air link resource structure information  1852 . FDD air link resource structure information  1850  includes structure information for a plurality of uplink/downlink band pairs ((uplink band  1  information  1854 , downlink band  1  information  1856 ), . . . , (uplink band N information  1858 , downlink band N information  1860 )). TDD air link resource structure information  1852  includes structure information for a plurality of uplink/downlink band pairs ((uplink band  1  information  1862 , downlink band  1  information  1864 ), . . . , (uplink band M information  1866 , downlink band M information  1868 )). Uplink band  1  information  1862  includes frequency information  1870  and time slot information  1872 , while downlink band  1  information  1864  includes frequency information  1874  and time slot information  1876 . In some embodiments, for at least some UL/DL band pairs the frequency information is the same, but the time slot information is different, e.g., frequency information  1870  and frequency information  1874  identify the same set of OFDM tones, but time slot information  1872  identifies a first set of time slots while time slot information  1876  identifies a second set of time slots, and the first and second set of time slots are non-overlapping. 
     Threshold determination module  1822  determines if a signal having a power level over a threshold level is received in a predetermined period of time from a communications band, e.g., a WAN band which is being monitored by the receiver module  1802 . In some embodiments, the signal being evaluated for received power level is a particular type of signal or particular designated signal, e.g., a beacon signal or a specific broadcast channel signal. 
     Peer to peer communications band selection module  1830  selects a corresponding communications band, which corresponds to the monitored communications band, for peer to peer signaling, when the determination module  1822  determines that a signal having a signal power level over the threshold level is not received in the predetermined period of time. Information identifying selected corresponding communications band for peer to peer signaling  1844  is an output of peer to peer communications band selection module  1830 , which is used by the transmitter module  1804 , e.g., for tuner setting. 
     Peer to peer signal generation module  1832  generates a peer to peer signal, e.g., generated peer to peer signal  1846 , to be transmitted by transmitter module  1804  in the band identified by information  1844 . 
     Stored correlation information between monitored bands and peer to peer usage bands  1843  includes information indicating a corresponding band to be used for peer to peer signals if a measurement of monitored band meets a criteria. For example, a signal monitored in a downlink FDD band is detected and has a received power level below a predetermined threshold, the corresponding band, in some embodiments is a corresponding uplink band, e.g., the monitored band is the band identified by downlink band  1  information  1856  and the corresponding band to be used for peer to peer signaling is uplink band identified by uplink band information  1854 . As another example, consider a case where a band is, optionally, used throughout the system, e.g., as a function of system configuration and/or system loading. Wireless terminal  1800  may monitor for a signal in a WAN band, and if the signal is not detected, the wireless terminal may assume that the band is not being currently used for WAN signaling in the region, and may use the same communications band for peer to peer signaling. For example, consider wireless terminal  1800  does not detect the presence of a particular type of signal, e.g., an OFDM beacon signal, being monitored for in a particular downlink FDD band, then the corresponding band selected for peer to peer signaling may be the same band, e.g., the downlink band N identified by information  1860  can be and sometimes is, both the monitored band and the band selected for peer to peer signaling. 
     In some embodiments, e.g., an embodiment in which some bands are optionally used throughout the system for WAN signaling and are available for peer to peer signaling if unused for WAN signaling, the stored information  1843  indicates that a WAN communications band being monitored for peer to peer threshold determination is the same as a corresponding communications band to be used for peer to peer signaling. 
     In some embodiments, the stored information  1843  indicates that a WAN communications band being monitored for peer to peer threshold determination is different from a corresponding communications band to be used for peer to peer signaling. In some FDD WAN system embodiments, DL WAN bands of the FDD system are monitored by threshold determination module  1822  and the corresponding uplink band is an UL frequency band. For example, the threshold determination module  1822  monitors one or more of the DL bands identified by information ( 1856 , . . . ,  1860 ), and selects a corresponding band to use for peer to peer signaling from uplink bands ( 1854 , . . . ,  1858 ). For example, consider that the monitored band which satisfies the test criteria is the band identified by downlink band  1  information  1856 , the corresponding uplink band selected by selection module  1830  for peer to peer signaling is the band identified by uplink band  1  information  1854 . As another example, consider a TDD system embodiment, DL WAN bands of the TDD system are monitored by threshold determination module  1822  and the corresponding uplink band is an UL frequency band. For example, the threshold determination module  1822  monitors one or more of the DL bands identified by information ( 1864 , . . . ,  1868 ), and selects a corresponding band to use for peer to peer signaling from uplink bands ( 1862 , . . . ,  1866 ). For example, consider that the monitored band which satisfies the test criteria is the band identified by downlink band  1  information  1864 , the corresponding uplink band selected by selection module  1830  for peer to peer signaling is the band identified by uplink band  1  information  1862 . In some such TDD embodiments, the corresponding uplink band identified by information  1862  to be used for peer to peer signaling may use the same set of frequencies as the monitored downlink band; however uplink and downlink may map to different non-overlapping time slots. 
     Band monitoring module  1824  monitors communications bands to detect for the presence or absence of a signal or signals in the communications band. Signal strength measurement module  1826  measures signal strength corresponding to a band being monitored, e.g., obtaining a signal strength corresponding to a particular signal being monitored for. In some embodiments, a null signal strength measurement value indicates that the signal was not detected in the monitored band. Threshold test module  1828  compares a measured signal strength to a threshold level, e.g., a threshold stored in band selection threshold information  1842 . 
     In some embodiments, there are a plurality of communications bands which can be, and sometimes are, monitored, and if a signal detected in a first monitored communication band exceeds a threshold, the threshold determination module  1822  monitors a second communications band out of the plurality of communications bands. For example, the threshold test module  1828  detects a threshold exceeded condition and notifies the band monitoring module  1824  to switch to monitor a different one or the plurality of communications bands. In some such embodiments, the peer to peer communication band selection module  1832  selects one of the plurality of bands other than the first communications band for peer to peer signaling as a function of the monitoring of the second communications band. In some such embodiments, the selection module  1830  selects a communications band in which the threshold detection module  1822  does not detect a signal exceeding the threshold. In some other such embodiments, the selection module  1830  selects a corresponding communications band, which corresponds to a communications band in which the detection module  1822  does not detect a signal exceeding the threshold. 
     Received WAN signal  1   1834  and received WAN signal n  1836  are received signals which are evaluated by threshold determination module  1822 . In some embodiments a received WAN signal, e.g., received WAN signal  1   1834 , may be background and/or interference noise present on a monitored set of air link resources, e.g., a set of OFDM tones over a predetermined time interval, with the absence of a specific characteristic signal being present above a predetermined power level being indicative of a band&#39;s availability for peer to peer signaling. For example, the band monitoring module  1824  is set to monitor the DL band identified by DL band  1  information  1856  and received WAN signal  1   1834  is obtained; the band monitoring module  1824  is set to monitor the DL band identified by DL band N information  1860  and received WAN signal n  1836  is obtained. (Measured signal strength for WAN signal  1   1838 , measured signal strength for WAN signal n  1840 ) represent outputs from signal strength measurement module  1826  corresponding to signal ( 1834 ,  1836 ), respectively. Band selection threshold information  1842  includes limits, e.g., predetermined limits, used by threshold test module  1828  in determining whether the measured received signal level is such to allow or restrict peer to peer communications in a corresponding band. 
       FIG. 19  is a drawing of an exemplary wireless terminal  1900 , e.g., a mobile node supporting peer to peer communications, in accordance with various embodiments. Exemplary wireless terminal  1900  includes a receiver module  1902 , a transmitter module  1904 , a processor  1906 , user I/O devices  1908 , and a memory  1910  coupled together via a bus  1912  over which the various elements may exchange data and information. 
     Receiver module  1902 , e.g., an OFDM or CDMA wireless receiver, is coupled to receive antenna  1914  via which the wireless terminal  1900  receives signals. Received signals include peer to peer communications signals and/or WAN downlink signals. In some embodiments, received signals include communications information query response signals. 
     Transmitter module  1904 , e.g., an OFDM or CDMA wireless transmitter, is coupled to transmit antenna  1916  via which the wireless terminal  1900  transmits signals, e.g., generated peer to peer signals such as signal  1960 , to other wireless terminals operating in a peer to peer communications mode of operation. Transmitted signals also include WAN uplink signals directed to a base station. Transmitter module  1904 , in some embodiments, also transmits queries generated by communications information query generation module  1928  over a wireless communications link, said query being directed to a network device. 
     In some embodiments, the same antenna is used for both transmitter module  1904  and receiver module  1902 . In some embodiments multiple antenna are used for at least one of reception and transmission, e.g., as part of a MIMO configuration. 
     In some embodiments, wireless terminal  1900  includes GPS module  1903 , which is also coupled to bus  1912 . In such an embodiment, the GPS module  1903 , e.g., a GPS receiver module, is coupled to GPS antenna  1905  via which the GPS module  1903  receives GPS signals from GPS satellites, the received GPS signals being utilized by GPS module  1903  to obtain a position fix information of wireless terminal  1900 . In various embodiments, the GPS module  1903  is included as part of the location determination module  1922 . 
     User I/O devices  1908  include, e.g., microphone, keyboard, keypad, switches, camera, speaker, display, etc. User I/O devices  1908  allow a user of wireless terminal  1900  to input data/information, access output data/information, and control at least some function of the wireless terminal, e.g., initiate a peer to peer communications session. In some embodiments, the user of wireless terminal  1900  may, and sometimes does enter an approximate location of the wireless terminal  1900 , which is utilized by the location determination module  1922  in determining a location, e.g., determining a more precise location in a shorter time than would otherwise be required. In some such embodiments, the entered location is used for initialization purposes by the GPS module  1903 . 
     User I/O devices  1908  include a user input module  1909 . User input module  1909  generates a signal from user input which is used by the location determination module  1922 , e.g., the user may enter a street address, intersection, landsite, highway, zip code, etc. and the user input module generates and communicates such information in a signal to the location determination module. 
     Memory  1910  includes routines  1918  and data/information  1920 . The processor  1906 , e.g., a CPU, executes the routines  1918  and uses the data/information  1920  in memory  1910  to control the operation of the wireless terminal  1900  and implement methods, e.g., the method of flowchart  1600  of  FIG. 16 . 
     Routines  1918  include a location determination module  1922 , a communications band determination module  1924 , a look-up module  1926 , a communications information query generation module  1928 , a communications information query response processing module  1930 , an information updating module  1931  and a peer to peer signal generation module  1932 . 
     Data/information  1920  includes band/location association information  1934 , a received signal  1936 , a determined current location  1938 , information identifying a determined communications band to use for device communications  1940  and a generated peer to peer signal  1960 . Band/location association information  1934  includes a plurality of sets of location information matched with communications band information ((location  1  information  1942 , communications band information  1946 ), (location N information  1944 , communications band information  1948 )). Communications band information  1946  includes one or more sets of band information (band  1  information  1950 , . . . , band N information  1952 ). Each set of band information includes usage designation information, e.g., information identifying whether the band is used for WAN signaling exclusively, P-P signaling exclusively, or shared to be used concurrently by both WAN and peer to peer signaling. Band  1  information  1950  includes usage type designation information  1954 . Communications band information  1948  includes one or more sets of band information (band  1  information  1956 , . . . , band M information  1958 ). 
     In some embodiments, at least some of the usage type information indicates that the designation of usage for a band changes over time, e.g., in accordance with a predetermined schedule. For example, in one exemplary embodiment, one base station sector may support a plurality of bands associated with different carriers and during time intervals where a high level of WAN signaling is anticipated each of the carriers are dedicated to exclusive WAN signaling; however, during intervals of anticipated intermediate levels of WAN activity at least one of the carriers is associated with shared concurrent WAN and peer to peer signaling. In some such embodiments, during intervals of anticipated low levels of WAN signaling activity, at least one of the carriers is associated with exclusive use for peer to peer signaling. 
     Location determination module  1922  determines from a received signal a current location of the wireless terminal  1900 . For example, from received signal  1936  the location determination module  1922  determines determined current location  1938 . The received signal  1936  can be and sometimes is a GPS signal or a signal derived from a processed received GPS signal. The received signal  1936  can be, and sometimes is, a signal from user input module  1909 . The received signal  1936  can be, and sometimes is a cellular network signal, e.g., a cellular network signal conveying base station derived location information being communicated via receiver module  1902  to wireless terminal  1900 . 
     Communications band determination module  1924  determines, based on determined location information, a communications band or bands to be used for device communications. Communications band determination module  1924  includes, in some embodiments, a peer to peer communications band determination module  1925  and a WAN communications band determination module  1927 . Peer to peer communications band determination module  1925  determines a communications band to be used at the current location for peer to peer communications. WAN communications band determination module  1927  determines a communications band to be used at the current location for WAN communications. In some embodiments different communications bands are determined to be used for peer to peer and WAN communications at a determined current location, for at least some locations. 
     Look-up module  1926  performs a look-up operation using the current location of the wireless terminal  1900  to identify a communications band in the stored information associated with the current location. For example, the location determination module  1922  may determine determined current location  1938  which is used by look-up module  1926 , which associates the determined current location  1938  with one of the stored sets of location information (location  1  information  1942 , . . . location N information  1944 ), and then determines the corresponding band information associated with that location. For example, consider that the determined current location maps to location N information  1944 , then the communications band information  1948  is utilized by look-up module  1926  to find a band for the device to use. In some such embodiments, the type of device usage, e.g., peer to peer communications is a further input utilized by look-up module  1926  to identify a band. 
     Peer to peer signal generation module  1932  generates a peer to peer signal, e.g., signal  1960 , to be transmitted by transmitter module  1904  in an identified communications band designated to be used at the current location for peer to peer communications. 
     Communications information query generation module  1928  generates a communications information query to a network device, e.g., a base station, central control node, controller node, band allocation control node, system load balancing node, or communications system wireless terminal tracking node, said query including the current location of the wireless terminal. 
     Communications query response processing module  1930  recovers information from a received response from a network device. The recovered information is used by the communications band determination module  1924  to determine a communications band associated with the current location. In some embodiments, the recovered information identifies one or more bands to be used for peer to peer signaling. In some embodiments, the recovered information identifies one or more bands to be used for both peer to peer signaling and WAN signaling concurrently. In some embodiments, the recovered information identifies one or more bands to be used for peer to peer signaling exclusively. In some embodiments, the recovered information identifies one or more bands to be used for WAN signaling exclusively. 
     Information updating module  1931  updates a stored set of information, e.g., band/location association information  1934  to include information indicating the current location and the communications band or bands associated with the current location determined from the query response. 
     Band/location association information  1934  includes information associating locations with communications bands, at least some of the locations being associated with different communications bands. Wireless terminal  1900  supports peer to peer signaling, and the band/location association information  1934  includes information indicating communications bands to be used for peer to peer communications at a plurality of locations. Wireless terminal  1900  supports wide area network (WAN) signaling, and the band/location association information  1934  includes information indicating communications bands to be used for WAN communications at a plurality of locations. In some embodiments, the stored information  1934  indicates different frequency bands to be used for peer to peer and wide area network communications at at least one location. In some embodiments, the stored information  1934  indicates that the same frequency band is to be used for peer to peer and wide area network communications at at least one location. 
     While described in the context of an OFDM system, the methods and apparatus of various embodiments are applicable to a wide range of communications systems including many non-OFDM and/or non-cellular systems. Some exemplary systems include a mixture of technologies utilized in the peer to peer signaling, e.g., some OFDM type signals and some CDMA type signals. 
     In various embodiments nodes described herein are implemented using one or more modules to perform the steps corresponding to one or more methods, for example, receiving a WAN signal, selecting a WAN communications band to use for peer to peer signaling based on the received WAN signal, identifying from stored information a corresponding uplink band associated with a downlink band, monitoring for the absence of a WAN signal above a predetermined threshold in a WAN communications band, determining to use a WAN band for peer to peer signaling as a function of a received power measurement comparison to a threshold, performing a location determination, performing a communications band determination, etc. In some embodiments various features are implemented using modules. Such modules 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 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). 
     Numerous additional variations on the methods and apparatus described above will be apparent to those skilled in the art in view of the above descriptions. Such variations are to be considered within scope. The methods and apparatus of various embodiments may be, and in various embodiments are, used with CDMA, orthogonal frequency division multiplexing (OFDM), and/or various other types of communications techniques which may be used to provide wireless communications links between access nodes and mobile nodes. In some embodiments the access nodes are implemented as base stations which establish communications links with mobile nodes using OFDM and/or CDMA. In various embodiments the mobile nodes are implemented as notebook computers, personal data assistants (PDAs), or other portable devices including receiver/transmitter circuits and logic and/or routines, for implementing the methods of various embodiments.