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A communications system for transferring signals from a wireless transmitter to a hub station, comprising a wireless transmitter configured to transmit a data signal using multiple sub-carriers, a plurality of base stations each configured to receive the multiple sub-carrier data signal and relay th

A communications system for transferring signals from a wireless transmitter to a hub station, comprising a wireless transmitter configured to transmit a data signal using multiple sub-carriers, a plurality of base stations each configured to receive the multiple sub-carrier data signal and relay the multiple sub-carrier data signal to a hub station; and a hub station configured to receive and combine the multiple sub-carrier data signals from the plurality of base stations. The wireless transmitter may use an orthogonal frequency division modulation (OFDM) scheme to transmit portions of the data signal in parallel on multiple sub-carriers.

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We claim: 1. A communications system for transferring information from a wireless transmitter to a hub station, comprising: a plurality of wireless transmitters, each configured to transmit a data signal as successive OFDM symbols with training symbols included among the OFDM symbols; a plurality o

We claim: 1. A communications system for transferring information from a wireless transmitter to a hub station, comprising: a plurality of wireless transmitters, each configured to transmit a data signal as successive OFDM symbols with training symbols included among the OFDM symbols; a plurality of base stations, each configured to receive the OFDM symbols from the wireless transmitters located in a corresponding coverage area and relay the received OFDM symbols to the hub station, at least some of said base stations having overlapping coverage areas such that more than one base station can receive OFDM symbols from the same mobile transmitter; the hub station configured to receive the OFDM symbols from the base stations and demodulate the OFDM symbols and output an estimate of the data signals from the wireless transmitters, wherein each of the base stations is connected to the hub station by a substantially independent communications link and the hub station is configured to reduce differences in propagation delays between at least some of the communications links by measuring time differences of training symbols detected on the at least some communications links and buffering the symbols from the at least some communications links based on the measured time differences. 2. The communications system of claim 1 wherein the communications system is used as a mobile electronic gathering system, including a video camera and audio transducer coupled to at least one of the wireless transmitters, the at least one wireless transmitter being a mobile transmitter configured to receive video and audio signals from the video camera and audio transducer for inclusion in the data signal. 3. The communications system of claim 1 wherein at least some of the base stations are connected to the hub station by wired communications links. 4. The communications system of claim 1 wherein the hub station is configured to, after reducing the differences in propagation delays between the at least some communications links, combine signals received from the different base stations. 5. The communications system of claim 4 wherein at least some of the base stations are connected to the hub station by independent wired communications links having predetermined propagation delays, the hub station including buffering to substantially eliminate, prior to combining signals received on the communications links, any delay spread resulting from the predetermined propagations delays. 6. The communications system of claim 4 wherein the hub station is configured to adaptively combine the signals received from each of the base stations based on measured signals characteristics. 7. The communications system of claim 1 wherein the wireless transmitters share a common communications channel, the wireless transmitters each being configured to receive a common reference signal to synchronize sharing of the channel. 8. The communications system of claim 7 wherein the common reference signal is a GPS signal. 9. The communications system of claim 1 wherein the training symbols transmitted by the wireless transmitters include psuedo-random training symbols, the hub station being configured to determine, for at least some of the base stations, if the at least some of the base stations have received a transmission from the wireless transmitters by checking for the presence of the psuedo-random training symbols in signals received from the at least some of the base stations. 10. A method for processing data signals that are transmitted by a mobile wireless transmitter as a series of OFDM symbols with training symbols included among the OFDM symbols, said method comprising: (a) receiving at a plurality of base stations the data signals transmitted from the mobile wireless transmitter, and relaying the received data signals from the plurality of base stations to a hub station, the base stations each having a substantially independent communications link with the hub station over which the received data signals are relayed; (b) receiving at the hub station the data signals relayed from the plurality of base stations; (c) reducing differences in propagation delays between at least some of the communications links by measuring time differences of the training symbols included in the data signals relayed over communications links and buffering the data signals from the at least some communications links based on the measured time differences. 11. A receiver network for receiving from at least one wireless transmitter data signals that include successive OFDM symbols, comprising: a plurality of spaced apart base stations configured to substantially simultaneously receive the OFDM symbols from the at least one wireless transmitter and transmit the OFDM symbols to a hub station; the hub station configured to receive and demodulate the OFDM symbols from the base stations wherein each of the base stations is connected to the hub station by a substantially independent communications link and training symbols are included among the OFDM symbols, wherein the hub station is configured to reduce differences in propagation delays between the communications links by measuring time differences of training symbols detected on the communications links and buffering the symbols from the communications links based on the measured time differences. 12. The receiver network of claim 11 wherein the hub station is configured to perform a separate discrete Fourier transform on the OFDM symbols received from at least some of the different base stations, and combine the transformed symbols based on measured signal characteristics. 13. The receiver network of claim 12 wherein the hub station is configured to combine the transformed symbols based on noise characteristics of signals received from the independent wired links. 14. The receiver network of claim 12 wherein the hub station is configured to determine which base stations have received a transmission from the wireless transmitter by checking for the presence of the training symbols in signals received from the base stations. 15. The receiver network of claim 14 wherein the training symbols are predetermined psuedorandom symbols. 16. The receiver network of claim 14 wherein the training symbols comprise OFDM symbols having predetermined characteristics distinguishable from OFDM symbols used to transmit useful data, the hub station being configured to determine the presence of the training symbols by determining if the signal power of subcarriers associated with the at least one wireless transmitter exceed a threshold value. 17. A communications system for transferring information from a wireless transmitter to a hub station, comprising: a plurality of wireless transmitters, each configured to transmit a data signal as successive OFDM symbols; a plurality of base stations, each configured to receive the OFDM symbols from the wireless transmitters located in a corresponding coverage area and relay the received OFDM symbols to the hub station, at least some of said base stations having overlapping coverage areas such that more than one base station can receive OFDM symbols from the same mobile transmitter; the hub station configured to receive the OFDM symbols from the base stations and demodulate the OFDM symbols and output an estimate of the data signals from the wireless transmitters, wherein the hub station includes: (i) a plurality of parallel OFDM symbol processing circuits, each processing circuit being associated with a respective base station for receiving OFDM symbols therefrom and performing at least some demodulation steps on the received OFDM symbols, wherein the processing circuits each include a down converter for down converting the OFDM symbols received from the base station associated therewith, an analog to digital converter for converting the down converted OFDM symbols to digital signals, and a delay removal buffer for buffering the digital signals to accommodate for propagation differences between the different base stations and the hub station; and (ii) a summer for combining the outputs of the processing circuits to produce the estimate of the data signals from the wireless transmitters. 18. The communications system of claim 17 including a common reference source for providing a common clock signal to the delay removal buffers. 19. The communications system of claim 17 wherein the OFDM symbols include training symbols, the delay removal buffers being configured to buffer the digital signals based on timing of detected training symbols. 20. The communications system of claim 17 wherein each of the processing circuits includes a discrete Fourier transform module for performing a discrete Fourier transform on the symbols processed thereby. 21. The communications system of claim 17 wherein the hub station includes an adaptive combiner controller for receiving representations of the OFDM symbols received from each of the base stations and determining signal characteristics thereof, the processing circuits each including a complex weighting device tesponsive to the adaptive combiner controller for applying a weighting factor to the symbols processed thereby based on the determined signal characteristics. 22. The receiver network of claim 11 wherein at least one of the training symbols include at least two identical sub-symbols. 23. The method of claim 10 including: (d) combining the data signals at the hub station subsequent to reducing the differences in propagation delays.