referring to fig1 , an exemplary radio communication system is shown generally at 100 and includes a base station 102 , radio signal repeaters 104 , 106 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 , and mobile stations 134 , 136 , 138 , and 140 . in the embodiment shown , the mobile station 134 is in radio communication with the radio signal repeater 106 , the mobile station 136 is in radio communication with the radio signal repeaters 106 and 120 , and the mobile station 140 is in radio communication with the radio signal repeater 118 . generally , the base station 102 and the radio signal repeaters 104 , 106 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 have respective radio communication ranges that overlap and collectively communicate by radio with mobile stations such as the mobile stations 134 , 136 , 138 , and 140 in a coverage area 142 surrounding the base station 102 . the base station 102 , the radio signal repeaters 104 , 106 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 , and the mobile stations 134 , 136 , 138 , and 140 may be referred to simply as radio stations . referring to fig2 , the base station 102 ( also shown in fig1 ) is illustrated schematically , and in the embodiment shown includes a microprocessor 144 and program memory 146 , an input / output (“ i / o ”) module 148 , and configuration memory 150 . the program memory 146 in the embodiment shown includes random - access memory (“ ram ”) encoded with codes generally for directing the microprocessor 144 to carry out functions of the base station 102 . the i / o module 148 includes a radio communication port 152 in communication with a radio antenna 154 . the i / o module 148 also includes a backhaul port 156 for communicating with a backhaul 158 of the base station 102 . the backhaul 158 connects the base station 102 to other base stations in a radio communication network and to other communication networks , such as telephone networks and the internet for example , to facilitate communication between mobile stations in the coverage area 142 ( shown in fig1 ) with mobile stations ( not shown ) outside of the coverage area ( 142 ) and with other telephones and computers on the internet ( not shown ), for example . the configuration memory 150 in the embodiment shown is also a ram , and generally stores data for configuring the base station 102 . although the base station 102 in the embodiment shown includes the microprocessor 144 , the program memory 146 , the i / o module 148 , and the configuration memory 150 , alternative base stations may include additional or alternative components such as hard drives and application - specific integrated circuits (“ asics ”), for example . referring to fig1 and 2 , the radio antenna 154 in the embodiment shown facilitates radio communication with the radio signal repeaters 104 , 106 , 108 , 110 , and 112 on at least five different radio channels , namely first and second downlink radio channels 160 and 162 , first and second uplink radio channels 164 and 166 , and a configuration and control radio channel 204 . although for simplicity the radio channels 160 , 162 , 164 , 166 , and 204 are illustrated in fig1 only between the base station 102 and the radio signal repeater 106 and between the radio signal repeaters 106 and 120 , in the embodiment shown the base station 102 is also in radio communication with the radio signal repeaters 106 , 108 , 110 , and 112 , the radio signal repeater 104 is in radio communication with the radio signal repeaters 114 and 116 , the radio signal repeater 106 is in radio communication with the radio signal repeaters 118 and 120 , the radio signal repeater 108 is in radio communication with the radio signal repeaters 122 and 124 , the radio signal repeater 110 is in radio communication with the radio signal repeaters 126 and 128 , and the radio signal repeater 112 is in radio communication with the radio signal repeaters 130 and 132 , all on the radio channels 160 , 162 , 164 , 166 , and 204 . the radio antenna 154 thus functions as a radio communication interface , or simply as an interface , to the radio signal repeaters 104 , 106 , 108 , 110 , and 112 in the embodiment shown . herein , “ radio channel ” refers to a multiplexed communication channel in one or more radio or other electromagnetic frequency bands . in the embodiment shown , the base station 102 is configurable to multiplex the radio channels 160 , 162 , 164 , and 166 using frequency - division multiplexing , in which case the radio channels 160 , 162 , 164 , and 166 are multiplexed onto respective different radio frequency bands . the base station 102 in the embodiment shown is also configurable to multiplex the radio channels 160 , 162 , 164 , and 166 using time - division multiplexing , in which case the first downlink radio channel 160 and the first uplink radio channel 164 are time - division multiplexed in a first radio frequency band , and the second downlink radio channel 162 and the second uplink radio channel 166 are time - division multiplexed in a second radio frequency band different from the first radio frequency band . however , in any case in the embodiment shown , the configuration and control radio channel 204 is multiplexed in a frequency band different from frequency bands of the radio channels 160 , 162 , 164 , and 166 . alternative base stations may multiplex the radio channels 160 , 162 , 164 , 166 , and 204 using different multiplexing techniques , and the configuration memory 150 in the embodiment shown stores configuration data specifying a particular multiplexing technique for the base station 102 . in the embodiment shown , the radio channels 160 , 162 , 164 , 166 , and 204 are in respective radio frequency bands in a radio frequency band between about 57 ghz and about 64 ghz , which may be referred to for simplicity as the “ 60 ghz ” band and which is unlicensed in the united states . in alternative embodiments , the radio channels 160 , 162 , 164 , 166 , and 204 may have other radio frequencies , such as other radio frequencies known as extremely high frequencies (“ ehf ”) between about 30 ghz and 300 ghz , for example . the respective radio frequency bands of the radio channels 160 , 162 , 164 , 166 , and 204 are also specified in the configuration memory 150 in the embodiment shown . referring back to fig2 , the program memory 146 includes downlink codes 168 that include blocks of code for directing the microprocessor 144 to transmit a downlink signal . referring to fig3 , the downlink codes 168 are illustrated schematically and begin at 170 in response to receiving a downlink message from the backhaul 158 ( shown in fig2 ). a downlink message received at 170 from the backhaul ( 158 ) may include any message directed to a mobile station in the coverage area 142 ( such as the mobile stations 134 , 136 , 138 and 140 shown in fig1 ), and may include a voice message , a data message , or a configuration message , for example . the downlink codes 168 continue at block 172 , which directs the microprocessor ( 144 ) to cause the radio antenna 154 to transmit a downlink signal encoded with the downlink message received at 170 on the first downlink radio channel 160 . the downlink codes 168 continue at block 174 , which directs the microprocessor ( 144 ) to transmit a downlink signal encoded with the downlink message received at 170 on the second downlink radio channel 162 . the downlink codes 168 then end . therefore , in the embodiment shown , the base station ( 102 ) receives a downlink message from the backhaul ( 158 ), and the base station ( 102 ) transmits downlink signals including that message on both the first and second downlink radio channels 160 and 162 . alternative base stations may transmit a signal on only one of the first and second downlink radio channels 160 and 162 , in which case one of the blocks 172 and 174 may be omitted . still other alternative base stations may select one of the first and second downlink radio channels 160 and 162 for downlink signals directed to particular radio signal repeaters in radio communication with the base station . referring to fig4 , an exemplary downlink signal transmitted in response to the codes in block 172 or 174 ( shown in fig3 ) is shown generally at 176 , and includes a destination identifier field 178 for storing an identifier of a destination for the downlink signal , and a message field 180 storing the message received at 170 ( shown in fig3 ). downlink signals in the embodiment shown are therefore digital data packets . however , in alternate embodiments , downlink signals may be analog signals or digital data stream signals that are not transmitted as digital data packets , for example . referring back to fig2 , the program memory 146 also includes uplink codes 182 for directing the microprocessor 144 ( shown in fig2 ) to receive an uplink signal from one of the radio signal repeaters 104 , 106 , 108 , 110 , and 112 ( shown in fig1 ) in the embodiment shown . referring to fig5 , the uplink codes 182 are illustrated schematically and begin either at 184 in response to an uplink signal received on the first uplink radio channel 164 at the radio antenna 154 ( shown in fig2 ) or at 186 in response to an uplink signal received on the second uplink radio channel 166 at the radio antenna ( 154 ). in either case , the uplink codes 182 continue at block 188 , which directs the microprocessor ( 144 ) to transmit the message encoded in the signal that was received at either 184 or 186 to the backhaul 158 ( shown in fig2 ). therefore , referring back to fig1 , in the embodiment shown the base station 102 receives uplink signals on the first and second uplink radio channels 164 and 166 from the radio signal repeaters 104 , 106 , 108 , 110 , and 112 , and transmits messages encoded in those uplink signals to the backhaul 158 ( shown in fig2 ). referring to fig6 , an exemplary uplink signal received at 184 or 186 ( shown in fig5 ) is shown generally at 190 , and includes a source identifier field 192 for storing an identifier of a source ( such as one of the mobile stations 134 , 136 , 138 , and 140 shown in fig1 , for example ) of an uplink message , and a message field 194 for storing the message . an uplink message in the uplink message field 194 may include data for voice communication or other data , for example . also , in the embodiment shown , the uplink signal 190 is a digital packet , but in alternative embodiments , uplink signals may include analog signals or digital data stream signals that are not divided into packets , for example . referring back to fig2 , the program memory 146 also includes configuration codes 196 for directing the microprocessor 144 ( shown in fig2 ) to receive and transmit configuration information . herein , “ configuration information ” may also refer to control information , and a “ configuration signal ” may also refer to a signal including control information . referring to fig7 , the configuration codes 196 in the embodiment shown begin at 198 in response to receiving configuration information from the backhaul 158 ( shown in fig2 ). configuration information received at 198 may include configuration information specifying multiplexing techniques , frequency bands for the radio channels 160 , 162 , 164 , 166 , and 204 , and generally other configuration information for the radio communication system 100 ( shown in fig1 ), for example . the configuration codes 196 continue at block 200 , which directs the microprocessor 144 ( shown in fig1 ) to store the configuration information received at 198 in the configuration memory 150 ( shown in fig2 ). the configuration codes 196 continue at block 202 , which directs the microprocessor ( 144 ) to transmit a configuration signal encoded with the configuration information on the configuration and control radio channel 204 . as indicated above , the configuration and control radio channel 204 in the embodiment shown is also between about 57 ghz and about 64 ghz , but is in a frequency band different from frequency bands of the radio channels 160 , 162 , 164 , and 166 . therefore , in the embodiment shown , configuration information is sent in a different radio frequency band from uplink and downlink signals , which may advantageously permit greater flexibility for timing configuration signals in some embodiments . alternatively , the configuration and control radio channel 204 could be multiplexed in the same radio frequency bands as the radio channels 160 , 162 , 164 , and 166 , for example . referring to fig8 , an exemplary configuration signal transmitted at block 202 ( shown in fig7 ) is shown generally at 326 , and includes a configuration information field 208 for storing configuration information such as the configuration information received at 198 ( shown in fig7 ). referring to fig9 , the radio signal repeater 106 ( also shown in fig1 ) is shown schematically and in the embodiment shown includes a microprocessor 210 and configuration memory 212 , program memory 214 , temporary memory 216 , and an i / o module 218 all in communication with the microprocessor 210 . the configuration memory 212 in the embodiment shown includes ram and stores information for configuring the radio signal repeater 106 such as configuration information received in the configuration signal 206 ( shown in fig8 ), for example . the program memory 214 in the embodiment shown also includes ram and stores codes generally for directing the microprocessor 210 to carry out functions of the radio signal repeater 106 . the temporary memory 216 in the embodiment shown includes ram and stores various data that are generated and accessed during operation of the radio signal repeater 106 . the i / o module 218 includes a radio antenna port 220 in communication with a radio antenna 222 , and in the embodiment shown the radio antenna 222 facilitates radio communication with the base station 102 and with the radio signal repeaters 118 and 120 ( shown in fig1 ) over the radio channels 160 , 162 , 164 , 166 , and 204 . the radio antenna 222 thus functions as a radio communications interface , or simply as an interface , for radio communication with the base station ( 102 ) and with the radio signal repeaters ( 118 and 120 ). although the radio signal repeater 106 is illustrated in the embodiment shown with the microprocessor 210 , the configuration memory 212 , the program memory 214 , the temporary memory 216 , and the i / o module 218 , alternative radio signal repeaters may include different components such as hard drives and asics , for example . the program memory 214 includes downlink codes 224 generally for directing the microprocessor 210 to respond to a downlink signal transmitted by the base station 102 ( shown in fig1 ) at block 172 or 174 ( shown in fig3 ) in the embodiment shown . referring to fig1 , the downlink codes 224 are illustrated schematically and begin either at 226 in response to receiving a downlink signal 176 ( shown in fig4 ) at the radio antenna 222 ( shown in fig9 ) on the first downlink radio channel 160 in response to the codes at block 172 ( shown in fig3 ), or at 228 in response to receiving a downlink signal ( 176 ) on the second downlink radio channel 162 in response to the codes at block 174 ( shown in fig3 ). if the downlink codes 224 begin at 226 , then the downlink codes 224 continue at block 230 , which directs the microprocessor 210 ( shown in fig9 ) to measure a signal - to - noise ratio of the signal received on the first downlink radio channel 160 , and to store the signal - to - noise ratio in a first signal - to - noise ratio store 232 in the temporary memory 216 ( shown in fig9 ). the downlink codes 224 continue at block 234 , which directs the microprocessor ( 210 ) to determine whether a signal encoded with the same data was also received on the second downlink radio channel 162 . a signal encoded with the same data may also be received on the second downlink radio channel 162 in response to the codes at block 174 ( shown in fig3 ). if at block 234 a signal encoded with the same data was also received on the second downlink radio channel 162 , then the downlink codes 224 also begin at 228 and continue at block 236 , which directs the microprocessor ( 210 ) to measure a signal - to - noise ratio of the signal on the second downlink radio channel 162 , and to store the signal - to - noise ratio in a second signal - to - noise ratio store 238 in the temporary memory 216 ( shown in fig9 ). the downlink codes 224 continue from block 236 to block 240 , which directs the microprocessor ( 210 ) to determine whether a signal encoded with the same data was also received on the first downlink radio channel 160 . if at block 234 a signal encoded with the same data was also received on the second downlink radio channel 162 , or if at block 240 a signal encoded with the same data was also received on the first downlink radio channel 160 , then the downlink codes 224 continue at block 242 , which directs the microprocessor ( 210 ) to determine whether the signal on the first downlink radio channel 160 was stronger than the signal on the second downlink radio channel 162 . in the embodiment shown , the codes at block 242 direct the microprocessor ( 210 ) to compare the signal - to - noise ratios stored in the first and second signal - to - noise ratio stores 232 and 238 ( shown in fig9 ), and the microprocessor ( 210 ) determines that the signal on the first downlink radio channel 160 is stronger than the signal on the second downlink radio channel 162 if the first signal - to - noise ratio store ( 232 ) stores a greater signal - to - noise ratio than the second signal - to - noise ratio store ( 238 ). if at block 242 the signal on the first downlink radio channel 160 is stronger than the signal on the second downlink radio channel 162 , or if at block 234 there is no signal encoded with the same data on the second downlink radio channel 162 , then the downlink codes 224 continue at block 244 , which directs the microprocessor ( 210 ) to configure an uplink transmit radio channel . store 246 in the temporary memory 216 ( shown in fig9 ) to set the first uplink radio channel 164 as the uplink transmit radio channel . the downlink codes 224 continue at block 248 , which directs the microprocessor ( 210 ) to configure a downlink receive radio channel store 250 in the temporary memory 216 ( shown in fig9 ) to set the first downlink radio channel 160 as the downlink receive radio channel . referring back to fig1 , in the embodiment shown the radio signal repeater 106 is in radio communication with the mobile station 134 on a mobile station radio channel 252 . in the embodiment shown , the radio channels 160 . 162 , 164 , 166 , and 204 are in the 60 ghz band , whereas the mobile station radio channel 252 is in a gsm radio band at about 2 ghz . in alternative embodiments , radio signal repeaters may communicate with mobile stations in various radio frequency bands such as radio frequency bands for gsm , cdma , tdma , and ieee 802 . 11 or 802 . 16 , for example , and such mobile station radio channels will generally be in lower radio frequencies than the radio frequencies of the radio channels 160 , 162 , 164 , 166 , and 204 in the embodiment shown . referring back to fig1 , the downlink codes 224 continue from block 248 to block 254 , which directs the microprocessor ( 210 ) to determine whether the destination identifier in the destination identifier field 178 ( shown in fig4 ) of the signal received at 226 designates a downlink radio channel in the mobile station radio channel 252 . in the embodiment shown , the destination identifier in the destination identifier field ( 178 ) designates a downlink radio channel in the mobile station radio channel 252 if the destination identifier in the destination identifier field ( 178 ) designates a mobile station in radio communication with the radio signal repeater ( 106 ) on the mobile station radio channel 252 , such as the mobile station 134 shown in fig1 in the embodiment shown . if at block 254 the destination identifier in the destination identifier field ( 178 ) designates a downlink radio channel in the mobile station radio channel 252 , then the downlink codes 224 continue at block 256 , which directs the microprocessor ( 210 ) to configure a downlink transmit radio channel store 258 in the temporary memory 216 ( shown in fig9 ) to set the mobile station radio channel 252 as the downlink transmit radio channel . otherwise , the downlink codes 224 continue at block 260 , which directs the microprocessor ( 210 ) to configure the downlink transmit radio channel store ( 258 ) to set the second downlink radio channel 162 as the downlink transmit radio channel . after either block 256 or 260 , the downlink codes 224 continue at block 262 , which directs the microprocessor ( 210 ) to determine whether the signal - to - noise ratio of the downlink receive radio channel exceeds a threshold stored in a threshold store 264 in the configuration memory 212 ( shown in fig9 ). if the downlink receive radio channel was set as the first downlink radio channel 160 at block 248 , then the codes at block 262 compare the signal - to - noise ratio stored in the first signal - to - noise ratio store 232 to the threshold stored in the threshold store 264 . if at block 262 the signal - to - noise ratio of the downlink receive radio channel exceeds the threshold , then the downlink codes 224 continue at block 266 , which directs the microprocessor 210 to cause the radio antenna 222 ( shown in fig9 ) to transmit a downlink signal on the downlink transmit radio channel ( specified by the downlink transmit radio channel store 258 shown in fig9 ) by amplifying the signal received from the downlink receive radio channel ( specified by the downlink receive radio channel store 250 ). however , if at block 262 the signal - to - noise ratio of the downlink receive radio channel does not exceed the threshold , then the downlink codes 224 continue at block 268 , which directs the microprocessor ( 210 ) to cause the radio antenna ( 222 ) to transmit a downlink signal ( 176 ) on the downlink transmit radio channel ( specified by the downlink transmit radio channel store 258 shown in fig9 ) by digitally decoding the message received from the downlink receive radio channel ( specified by the downlink receive radio channel store 250 ) and encoding the decoded message for the downlink signal . after either block 266 or block 268 , the downlink codes 224 end . therefore , in the embodiment shown , the radio signal repeater ( 106 ) can repeat a received message either by simply amplifying the received uplink signal ( as at block 266 ), or by digitally decoding and then encoding the received message ( as at block 268 ). where the signal - to - noise ratio of the received signal is above a threshold , the radio signal repeater ( 106 ) may simply amplify the signal , as a signal with a higher signal - to - noise ratio may be expected to have fewer errors . however , where the signal - to - noise ratio is below the threshold , then the signal is more likely to include errors , and digitally decoding and encoding the message may advantageously enhance the quality of the repeated signal , particularly if the signal includes redundant data - correction information , for example . in alternative embodiments , the codes at block 262 may be omitted , and the downlink codes 224 may proceed directly to either the codes at block 266 or to the codes at block 268 , for example . in still other embodiments , the configuration memory 212 ( shown in fig9 ) may include configuration information determining whether to execute the codes at block 266 or the codes at block 268 . further , in embodiments where the downlink and uplink signals are purely analog , then the codes of blocks 262 and 268 may be omitted such that the downlink codes 224 proceed directly to the codes at block 266 . still referring to fig1 , if at block 240 a signal encoded with the same data was not also received on the first downlink radio channel 160 , or if at block 242 the signal on the first downlink radio channel 160 was not stronger than the signal on the second downlink radio channel 162 , then the downlink codes 224 continue at block 270 , which directs the microprocessor ( 210 ) to configure the uplink transmit radio channel store 246 ( shown in fig9 ) to set the second uplink radio channel 166 as the uplink transmit radio channel . the downlink codes 224 continue at block 272 , which directs the microprocessor ( 210 ) to configure the downlink receive radio channel store 250 ( shown in fig9 ) to set the second downlink radio channel 162 as the downlink receive radio channel . the downlink codes 224 continue at block 274 , which directs the microprocessor ( 210 ) to determine whether the destination identifier in the destination identifier field 178 of the downlink signal 176 ( shown in fig4 ) received at 228 designates a downlink radio channel in the mobile station radio channel 252 . the codes at block 274 are therefore substantially the same as the codes at block 254 , except that the codes at block 254 direct the microprocessor ( 210 ) to respond to the destination identifier in the destination identifier field ( 178 ) of a downlink signal ( 176 ) received at 226 , and the codes at block 274 direct the microprocessor ( 210 ) to respond to the destination identifier in the destination identifier field ( 178 ) of a downlink signal ( 176 ) received at 228 . if at block 274 the destination identifier in the destination identifier field ( 178 ) designates a downlink radio channel in the mobile station radio channel 252 , then the downlink codes 224 continue at block 256 as discussed above . otherwise , the downlink codes 224 continue at block 276 , which directs the microprocessor ( 210 ) to configure the downlink transmit radio channel store 258 ( shown in fig9 ) to set the first downlink radio channel 160 as the downlink transmit radio channel . the downlink codes 224 then continue at block 262 as described above , except that if the downlink receive radio channel was set as the second downlink radio channel 162 at block 272 , then the codes at block 262 compare the signal - to - noise ratio stored in the second signal - to - noise ratio store 238 ( shown in fig9 ) to the threshold stored in the threshold store 264 ( shown in fig9 ). referring back to fig1 , the radio signal repeater 106 in the embodiment shown may also receive uplink signals from the radio signal repeaters 118 and 120 or from the mobile stations 134 and 136 . referring to fig1 and 9 , the program memory 214 also includes uplink codes 278 generally for directing the microprocessor 210 to respond to an uplink signal 190 ( shown in fig6 ) from one of the radio signal repeaters 118 and 120 or from one of the mobile stations 134 and 136 in the embodiment shown . referring to fig1 , the uplink codes 278 are illustrated schematically and begin at one of : 280 in response to receiving an uplink signal ( 190 ) at the radio antenna 222 ( shown in fig9 ) on the first uplink radio channel 164 ; 282 in response to receiving an uplink signal ( 190 ) at the radio antenna ( 222 ) on the second uplink radio channel 166 ; and 284 in response to receiving an uplink signal ( 190 ) at the radio antenna ( 222 ) on the mobile station radio channel 252 . after either 280 , 282 , or 284 , the uplink codes 278 continue at block 288 , which directs the microprocessor ( 210 ) to measure a signal - to - noise ratio of the uplink signal received at 280 , 282 , or 284 . the uplink codes 278 continue at block 290 , which directs the microprocessor ( 210 ) to determine whether the signal - to - noise ratio determined that block 288 exceeds the threshold stored in the threshold store 264 ( shown in fig9 ). if at block 290 the signal - to - noise ratio exceeds the threshold , then the uplink codes 278 continue at block 292 , which directs the microprocessor ( 210 ) to transmit an uplink signal 190 ( shown in fig6 ) on the uplink transmit radio channel ( specified by the uplink transmit radio channel store 246 shown in fig9 ) by amplifying the signal received at 280 , 282 , or 284 . otherwise , the uplink codes 278 continue at block 294 , which directs the microprocessor ( 210 ) to transmit an uplink signal ( 190 ) on the uplink transmit radio channel ( specified by the uplink transmit radio channel store 246 ) by digitally decoding the message received at 280 , 282 , or 284 , and then encoding the decoded message . therefore , as discussed above with respect to blocks 262 , 266 , and 268 ( shown in fig1 ), the codes at blocks 290 , 292 , and 294 cause the microprocessor ( 210 ) simply to amplify a received uplink signal if the signal - to - noise ratio of the received uplink signal exceeds a threshold , but to digitally decode and encode the received message if the signal - to - noise ratio of the received uplink signal is less than the threshold , as a signal received with a lower signal - to - noise ratio is likely to have additional errors that may be removed by digitally decoding and encoding the message . again , in alternative embodiments , the codes at block 290 may be omitted , and the uplink codes 278 may proceed directly to either the codes at block 292 or to the codes at block 294 , for example . in still other embodiments , the configuration memory 212 ( shown in fig9 ) may include configuration information determining whether to execute the codes at block 292 or the codes at block 294 . further , in embodiments where the downlink and uplink signals are purely analog , then the codes of blocks 290 and 294 may be omitted such that the uplink codes 278 proceed directly to the codes at block 292 . referring back to fig9 , the program memory 214 also includes configuration codes 296 generally for directing the microprocessor 210 to respond to a configuration signal 206 ( shown in fig8 ) transmitted in response of the codes at block 202 ( shown in fig7 ), for example . referring to fig1 , the configuration codes 296 are illustrated schematically and begin at 298 in response to receiving a configuration signal ( 206 ) at the radio antenna 222 ( shown in fig9 ). the configuration codes 296 continue at block 300 , which direct the microprocessor 210 ( shown in fig9 ) to store the configuration information of the configuration information field 208 ( shown in fig8 ) of the configuration signal ( 206 ) received at 298 in the configuration memory 212 ( shown in fig9 ). the configuration codes 296 continue at block 302 , which directs the microprocessor ( 210 ) to cause the radio antenna ( 222 ) to transmit a configuration signal ( 206 ) on the configuration and control radio channel 204 . in the embodiment shown , the codes at block 302 cause the radio signal repeater 106 to transmit the configuration signal ( 206 ) to the radio station repeaters 118 and 120 shown in fig1 . referring back to fig1 , the radio signal repeaters 104 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 are substantially the same as the radio signal repeater 106 in the embodiment shown . however , in operation , the radio signal repeaters 104 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 in the embodiment shown communicate by radio with other such radio stations as shown in fig1 and described above . referring to fig1 , the mobile station 136 is illustrated schematically and in the embodiment shown includes a microprocessor 304 and configuration memory 306 for storing configuration information for the mobile station 136 , program memory 308 generally for directing the microprocessor 304 to carry out functions of the mobile station 136 , temporary memory 310 for storing data generated and accessed during operation of the mobile station 136 , and an i / o module 312 , all in communication with the microprocessor 304 . the configuration memory 306 , the program memory 308 , and the temporary memory 310 in the embodiment shown are ram , and the i / o module 312 includes a radio antenna port 314 for communicating with a radio antenna 316 . the mobile station 136 also includes a user interface 317 in communication with the i / o module 312 . the user interface 317 represents various i / o components for interacting with a user of the mobile station 136 , and in the embodiment shown includes a screen , a microphone , a speaker , and a keypad ( all not shown ). referring to fig1 and 13 , the radio antenna 316 in the embodiment shown facilitates radio communication with the radio signal repeaters 106 and 120 . however , unlike the mobile station 134 , the mobile station 136 is in radio communication with the radio signal repeaters 106 and 120 on the radio channels 160 , 162 , 164 , 166 , and 204 . in alternative embodiments , the mobile station 136 may be in radio communication with other radio signal repeaters or base stations , and more generally the radio antenna 316 functions as a radio communication interface , or simply an interface , for radio communication with radio signal repeaters such as the radio signal repeaters 106 and 120 . referring back to fig1 , the program memory 308 includes downlink codes 318 generally for directing the microprocessor 304 to respond to a downlink signal 176 ( shown in fig4 ) transmitted in response to the codes at block 266 or 268 ( shown in fig1 ) in the embodiment shown . referring to fig1 , the downlink codes 318 are illustrated schematically and begin either at 320 in response to receiving a downlink signal ( 176 ) at the radio antenna 316 ( shown in fig1 ) on the first downlink radio channel 160 , or at 322 in response to receiving a downlink signal ( 176 ) at the radio antenna ( 316 ) on the second downlink radio channel 162 . if the downlink codes 318 begin at 320 , then the downlink codes 318 continue at block 324 , which directs the microprocessor 304 ( shown in fig1 ) to configure an uplink transmit radio channel store 326 in the temporary memory 310 ( shown in fig1 ) to set the first uplink radio channel 164 as the uplink transmit radio channel . the codes at block 324 direct the microprocessor ( 304 ) to set the first uplink radio channel 164 as the uplink transmit radio channel in response to a downlink signal received on the first downlink radio channel 160 , and the first uplink radio channel 164 is thus associated with the first downlink radio channel 160 . the downlink codes 318 continue at block 328 , which directs the microprocessor ( 304 ) to respond to the downlink signal ( 176 ) received at 320 or 322 . for example the downlink signal ( 176 ) received at 320 or 322 may include a message for voice communication or for other data transmission , and the codes at block 328 generally direct the microprocessor ( 304 ) to respond to the message accordingly . however , if the downlink codes 318 begin at 322 , then the downlink codes 318 continue at block 330 , which directs the microprocessor ( 304 ) to configure the uplink transmit radio channel store ( 326 ) to set the second uplink radio channel 166 as the uplink transmit radio channel . the codes at block 330 direct the microprocessor ( 304 ) to set the second uplink radio channel 166 as the uplink transmit radio channel in response to a downlink signal received on the second downlink radio channel 162 , and the second uplink radio channel 166 is thus associated with the second downlink radio channel 162 . the downlink codes 318 then continue at block 328 as described above . referring back to fig1 , the program memory 308 also includes uplink codes 332 generally for directing the microprocessor 304 to transmit an uplink signal 190 ( shown in fig6 ). referring to fig1 , the uplink codes 332 are illustrated schematically and begin at 334 in response to receiving an uplink message . the uplink message received at 334 may include uplink data for voice communication or other data communicated from the mobile station ( 136 ), for example . the uplink codes 332 continue at block 336 , which direct the microprocessor 304 ( shown in fig1 ) to transmit an uplink signal ( 190 ) including the uplink message received at 334 in the message field 194 ( shown in fig6 ) of the uplink signal ( 190 ) on the uplink transmit radio channel specified by the uplink transmit radio channel store 326 ( shown in fig1 ). the uplink codes 332 then end . referring back to fig1 , the program memory 308 also includes configuration codes 338 generally for directing the microprocessor 304 to respond to a configuration signal 206 ( shown in fig8 ) received at the radio antenna 316 on the configuration and control radio channel 204 in response to the codes at block 202 ( shown in fig7 ), for example . referring to fig1 , the configuration codes 338 are illustrated schematically and begin at 340 in response to receiving the configuration signal ( 206 ) from the radio antenna ( 316 ). the configuration codes 338 continue at block 342 , which directs the microprocessor 304 ( shown in fig1 ) to store configuration information from the configuration information field 208 of the configuration signal 206 ( shown in fig8 ) received at 340 in the configuration memory 306 ( shown in fig1 ). the configuration codes 338 then end . referring to fig1 , an illustrative sequence of signals transmitted and received in the radio communication system 100 ( shown in fig1 ) is illustrated schematically and shown generally at 344 . the sequence of signals 344 begins when the base station 102 transmits a first downlink signal 346 on the first downlink radio channel 160 encoded with a first message 348 in response to the codes of block 172 of the downlink codes . 168 ( shown in fig3 ). the radio signal repeater 106 receives the first downlink signal 346 and transmits a second downlink signal 350 on the second downlink radio channel 162 encoded with the first message 348 in response to the codes at blocks 230 , 234 , 244 , 248 , 254 , 260 , 262 , and either 266 or 268 of the downlink codes 224 ( shown in fig1 ). the mobile station 136 receives the second downlink signal 350 in response to the codes at blocks 330 and 328 of the downlink codes 318 ( shown in fig1 ). the mobile station 136 then transmits a first uplink signal 352 encoded with a second message 354 on the second uplink radio channel 166 in response to the codes at block 336 of the uplink codes 332 ( shown in fig1 ). then the radio signal repeater 106 receives the first uplink signal 352 and transmits a second uplink signal 356 on the first uplink radio channel 164 encoded with the second message 354 in response to the uplink codes 278 ( shown in fig1 ). the base station 102 then receives the second uplink signal 356 in response to the uplink codes 182 ( shown in fig5 ). in summary , in the sequence of signals 344 , the radio signal repeater 106 : receives , from the base station 102 , the first downlink signal 346 encoded with the first message 348 on the first downlink radio channel 160 ; after receiving the first downlink signal 346 , transmits , to the mobile station 136 , the second downlink signal 350 encoded with the first message 348 on the second downlink radio channel 162 ; receives , from the mobile station 136 , the first uplink signal 352 encoded with the second message 354 on the second uplink radio channel 166 ; and after receiving the first uplink signal 352 , transmits , to the base station 102 , the second uplink signal 356 encoded with the second message 354 on the first uplink radio channel 164 . in an alternative embodiment also shown on fig1 , the base station 102 also transmits a third downlink signal 358 on the second downlink radio channel 162 and encoded with the first message 348 , and the radio signal repeater 106 receives the third downlink signal 358 before transmitting the second downlink signal 350 . however , in this alternative embodiment , the radio signal repeater 106 measures ( at block 230 shown in fig1 ) a higher signal - to - noise ratio of the first downlink signal 346 than for the third downlink signal 358 ( measured at block 236 shown in fig1 ). therefore , at block 242 shown in fig1 , the radio signal repeater 106 determines that the first downlink signal 346 on the first downlink radio channel 160 is stronger than the third downlink signal 358 on the second downlink radio channel 162 , and the downlink codes 224 therefore continue at blocks 244 , 248 , 254 , 260 , 262 , and 266 or 268 ( shown in fig1 ) in this alternative embodiment . therefore , in this alternative embodiment , the radio signal repeater 106 also receives , before transmitting the second radio signal ( the second downlink signal 350 ), a fifth radio signal ( the third downlink signal 358 ) encoded with the first message 348 on the second radio channel ( the second downlink radio channel 162 ), but because the first signal ( the first downlink signal 346 ) is stronger than the fifth signal ( the third downlink signal 358 ), the codes at block 242 ( shown in fig1 ) cause the radio signal repeater 106 to select ( at block 260 shown in fig1 ) the second radio channel ( the second downlink radio channel 162 ) instead of the first channel ( the first downlink channel 160 ) for the second radio signal ( the second downlink signal 350 ). referring back to fig1 , the mobile station 136 is also in radio communication with the radio signal repeater 120 on the radio channels 160 , 162 , 164 , 166 , and 204 , and due to interference or other environmental conditions , for example , the mobile station 136 may lose radio communication with the radio signal repeater 106 and begin receiving downlink signals instead from the radio signal repeater 120 . referring to fig1 , another illustrative sequence of signals transmitted and received in the radio communication system 100 ( shown in fig1 ), where the mobile station 136 receives downlink signals from the radio signal repeater 120 instead of from the radio signal repeater 106 , is illustrated schematically and shown generally at 374 . the sequence of signals 374 begins when the base station 102 transmits a first downlink signal 376 on the first downlink radio channel 160 encoded with a first message 378 . the radio signal repeater 106 receives the first downlink signal 346 and transmits a second downlink signal 380 on the second downlink radio channel 162 encoded with the first message 378 . the radio signal repeater 120 receives the second downlink signal 376 and transmits a third downlink signal 382 on the first downlink radio channel 160 encoded with the first message 378 . the mobile station 136 receives the third downlink signal 382 in response to the codes at blocks 324 and 328 of the downlink codes 318 ( shown in fig1 ). the mobile station 136 then transmits a first uplink signal 384 encoded with a second message 386 on the first uplink radio channel 164 in response to the codes at block 336 of the uplink codes 332 ( shown in fig1 ). then the radio signal repeater 120 receives the first uplink signal 384 and transmits a second uplink signal 388 on the second uplink radio channel 166 encoded with the second message 386 . then the radio signal repeater 106 receives the second uplink signal 388 and transmits a third uplink signal 390 on the first uplink radio channel 164 encoded with the second message 386 . the base station 102 then receives the third uplink signal 390 . in summary , in the sequence of signals 374 , the radio signal repeater 120 : receives the second downlink signal 380 from the radio signal repeater 106 ; after receiving the second downlink signal 380 , transmits the third downlink signal 382 encoded with the first message 378 to the mobile station 136 on the first downlink radio channel 160 ; and before transmitting the second uplink signal 388 , receives the first uplink signal 384 encoded with the second message 386 from the mobile station 136 . in summary , referring to fig1 and 18 , in the sequences of signals 344 and 374 , the mobile station 136 : receives the second downlink signal 350 from the radio signal repeater 106 on the second downlink radio channel 162 ; transmits the first uplink signal 352 to radio signal repeater 106 on the second uplink radio channel 166 associated ( by the codes at block 330 shown in fig1 ) with the second downlink radio channel 162 ; receives the third downlink signal 382 from the radio signal repeater 120 on the first downlink radio channel 160 ; and transmits the first uplink signal 384 to the radio signal repeater 120 on the first uplink radio channel 164 associated ( by the codes at block 324 shown in fig1 ) with the first downlink radio channel 160 . in the illustrative embodiments shown in fig1 and 18 , the radio signal repeaters communicate only in the radio channels 160 , 162 , 164 , and 166 , and therefore in such embodiments need not be configured to communicate in the mobile station radio channel 252 . therefore , in such embodiments , blocks 254 , 256 , and 274 ( shown in fig1 ) may be omitted . referring to fig1 , another illustrative sequence of signals transmitted and received in the radio communication system 100 ( shown in fig1 ) is illustrated schematically and shown generally at 360 . the sequence of signals 360 begins when the base station 102 transmits a first downlink signal 362 on the first downlink radio channel 160 and encoded with a first message 364 . in the embodiment shown , the destination identifier in the destination identifier field 178 ( shown in fig4 ) of the first downlink signal 362 designates the mobile station 134 , which is in radio communication with the radio signal repeater 106 over the mobile station radio channel 252 as shown in fig1 . therefore , the radio signal repeater 106 receives the first downlink signal 362 and transmits a second downlink signal 366 encoded with the first message 364 on the mobile station radio channel 252 in response to the codes at block 254 shown in fig1 . the mobile station 134 receives the second downlink signal 366 , and later transmits a first uplink signal 368 encoded with a second message 370 on the mobile station radio channel 252 . the radio signal repeater 106 receives the first uplink signal 368 and transmits a second uplink signal 372 encoded with the second message 370 on the first uplink radio channel 164 in response to the uplink codes 278 ( shown in fig1 ). the base station 102 then receives the second uplink signal 372 in response to the uplink codes 182 ( shown in fig5 ). in summary , in the illustrative sequence of signals 360 , the radio signal repeater 106 : receives the first downlink signal 362 encoded with the first message 364 on the first downlink radio channel 160 ; after receiving the first downlink signal 362 , transmits , to the mobile station 134 , the second downlink signal 366 encoded with the first message 364 on the mobile station radio channel 252 ; receives the first uplink signal 368 encoded with the second message 370 from the mobile station 134 on the mobile station radio channel 252 ; and after receiving the first uplink signal 368 , transmits , to the base station 102 , the second uplink signal 372 encoded with the second message 370 on the first uplink radio channel 164 . in the illustrative sequence of signals 360 , the mobile station 134 communicates on the mobile station radio channel 252 with the radio signal repeater 106 , and the mobile station 134 may thus be considered to be in a micro , pico , or femto cell of the radio signal repeater 106 . in the embodiment shown , one or more of the radio signal repeaters 104 , 106 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 may establish respective such micro , pico , or femto cells . referring back to fig1 , the mobile station 140 is in radio communication with the radio signal repeater 118 on the mobile station radio channel 252 . in the embodiment shown , the configuration information received at 198 ( shown in fig7 ) and transmitted in the configuration information field 208 ( shown in fig8 ), for example , may configure the mobile stations 134 and 140 to be in radio communication with the radio signal repeaters 106 and 118 on respective different subchannels of the mobile station radio channel 252 . more generally , in the embodiment shown , the configuration information may associate various subchannels of the mobile station radio channel 252 with each of the radio signal repeaters 104 , 106 , 108 , 110 , 112 , 114 , 116 , 118 , 120 , 122 , 124 , 126 , 128 , 130 , and 132 , and one or more mobile stations in radio communication with one of those radio signal repeaters may also be associated with the subchannel associated with the radio signal repeater . these different subchannels may be advantageous to reduce interference in transmissions from adjacent radio signal repeaters on the mobile station radio channel 252 , for example . the configuration information may also associate the subchannels of the mobile station radio channel 252 with respective subchannels in each of the radio channels 160 , 162 , 164 , and 166 . in such a configuration , the codes at blocks 172 and 174 ( shown in fig3 ) and at blocks 266 and 268 ( shown in fig1 ) transmit downlink signals 178 ( shown in fig4 ) in respective subchannels of the first and second downlink radio channels 160 and 162 that are associated with the destination mobile station of the downlink signals , and the codes at blocks 292 and 294 ( shown in fig1 ) and at block 336 ( shown in fig1 ) transmit uplink signals 190 ( shown in fig6 ) in respective subchannels of the first and second uplink radio channels 164 and 166 that are associated with the source mobile station of the uplink signals . also in such a configuration , the destination identifier field 178 ( shown in fig4 ) and the source identifier field 192 ( shown in fig6 ) may be omitted because the destination or source of a signal may be identified by the subchannel of the downlink signal ( 178 ) or of the uplink signal ( 190 ), and the codes at blocks 254 and 274 ( shown in fig1 ) may determine whether the signal is designated for the mobile station radio channel 252 by identifying the subchannel of the transmit downlink signal ( 178 ) received at 226 or 228 ( also shown in fig1 ). referring to fig2 , another illustrative sequence of signals transmitted and received in the radio communication system 100 ( shown in fig1 ) is illustrated schematically and shown generally at 392 . the sequence of signals 392 begins when the base station 102 transmits a first downlink signal 394 in a subchannel of the first downlink radio channel 160 associated with the mobile station 134 . the radio signal repeater 106 receives the first downlink signal 394 and transmits a second downlink signal 396 to the mobile station 134 on a subchannel of the mobile station radio channel 252 associated with the mobile station 134 . later , the mobile station 134 transmits a first uplink signal 398 on the subchannel of the mobile station radio channel 252 associated with the mobile station 134 , and the radio signal repeater 106 receives the first uplink signal 398 and transmits a second uplink signal 400 to the base station 102 on a subchannel of the first uplink radio channel 162 associated with the mobile station 134 . later in the sequence of signals 392 , the base station 102 transmits a third downlink signal 402 on a subchannel of the first downlink radio channel 160 associated with the mobile station 140 . the radio signal repeater 106 receives the third downlink signal 402 and transmits a fourth downlink signal 404 on a subchannel of the second downlink radio channel 162 associated with the mobile station 140 . the radio signal repeater 118 receives the fourth downlink signal 404 and transmits a fifth downlink signal 406 to the mobile station 140 on a subchannel of the mobile station radio channel 252 associated with the mobile station 140 . later , the mobile station 140 transmits a third uplink signal 408 on the subchannel of the mobile station radio channel 252 associated with the mobile station 140 . the radio signal repeater 118 receives the third uplink signal 408 and transmits a fourth uplink signal 410 on a subchannel of the second uplink radio channel 166 associated with the mobile station 140 . the radio signal repeater 106 receives the fourth uplink signal 410 and transmits a fifth uplink signal 412 on a subchannel of the first uplink radio channel 164 associated with the mobile station 140 . the radio communication system 100 may enable communication at higher radio frequencies , such as ehf frequencies for example , advantageously enabling greater operating bandwidth available in such higher radio frequencies . in practice , the base station 102 of the radio communication system 100 may replace an existing base station using only lower radio frequencies to upgrade the existing base station and provide greater operating bandwidth . further , the radio signal repeaters described above may advantageously be positioned closer together , as may be required to accommodate the shorter range of higher radio frequencies , as the at least two different channels for uplink signals and the at least two different channels downlink signals may advantageously reduce interference between the signals . while various embodiments have been described and illustrated , such embodiments should be considered illustrative only and not as limiting the invention as construed in accordance with the accompanying claims .