Transmission and reception system with guard intervals containing known components unrelated to transmitted data

Abstract

A receiver receives a signal containing data distributed in both time and frequency. The receiver includes a vector transform arranged to perform a transform on the received signal using a plurality of receiver transform vectors. The receiver transform vectors are based upon a corresponding plurality of transmitter vectors modified in accordance with channel effects so that the data can be recovered by the vector transform even in the presence of strong ghosts.

What is claimed is:  
     
         1 . A receiver, wherein the receiver receives a signal containing data distributed in both time and frequency, the receiver comprising: 
 a vector transform arranged to perform a transform on the received signal using a plurality of transform vectors; and,    a vector adjuster responsive to the transform of the received signal in order to adjust the transform vectors so that the data can be recovered even in the presence of a strong ghost.    
     
     
         2 . The receiver of  claim 1  wherein the vector adjuster comprises a comparator arranged to compare the transform to a reference.  
     
     
         3 . The receiver of  claim 2  wherein the reference is a known block of data stored in the receiver.  
     
     
         4 . The receiver of  claim 3  wherein the reference is stored in a transmitter and is used to form a training signal that is used by the vector adjuster to adjust the transform vectors.  
     
     
         5 . The receiver of  claim 2  wherein the vector adjuster comprises a vector modifier arranged to modify the transform vectors in response to the comparator so that the transform vectors are modified to compensate for channel interference.  
     
     
         6 . The receiver of  claim 2  wherein the comparator produces comparison results, and wherein the vector adjuster comprises a gain block arranged to impose a fractional gain on the comparison results.  
     
     
         7 . The receiver of  claim 6  wherein the vector adjuster comprises a vector modifier arranged to modify the transform vectors in response to the comparator so that the transform vectors are modified to compensate for channel interference.  
     
     
         8 . The receiver of  claim 6  wherein the vector adjuster comprises a multiplier arranged to multiply an output of the gain block and the transform vectors.  
     
     
         9 . The receiver of  claim 8  wherein the multiplier produces multiplication results, and wherein the vector modifier comprises a summer arranged to sum the multiplication results and the transform vectors in order to adjust the transform vectors.  
     
     
         10 . The receiver of  claim 1  further comprising a switch arranged to interconnect the vector transform and the vector adjuster during vector adjustment.  
     
     
         11 . The receiver of  claim 1  wherein the vector transform performs a matrix multiplication of the received signal and the transform vectors.  
     
     
         12 . The receiver of  claim 1  wherein the vector adjuster is arranged to adjust the transform vectors in accordance with channel interference.  
     
     
         13 . A receiver, wherein the receiver receives a signal containing data distributed in both time and frequency, wherein the receiver includes a vector transform arranged to perform a transform on the received signal using a plurality of receiver transform vectors, and wherein the receiver transform vectors are based upon a corresponding plurality of transmitter vectors and channel effects so that the data can be recovered by the vector transform even in the presence of a strong ghost.  
     
     
         14 . The receiver of  claim 13  wherein the receiver transform vectors are the transmitter vectors modified according to channel effects.  
     
     
         15 . The receiver of  claim 13  wherein the receiver comprises a comparator arranged to compare the transform to a reference.  
     
     
         16 . The receiver of  claim 15  wherein the reference is a known block of data stored in the receiver.  
     
     
         17 . The receiver of  claim 16  wherein the reference is stored in a transmitter and is used to form a training signal that is used by the receiver to adjust the receiver transform vectors.  
     
     
         18 . The receiver of  claim 15  wherein the receiver further comprises a vector adjuster arranged to adjust the transform vectors in response to the comparator so that the receiver transform vectors are modified to compensate for channel interference.  
     
     
         19 . The receiver of  claim 15  wherein the comparator produces comparison results, and wherein the receiver further comprises a gain block arranged to impose a fractional gain on the comparison results.  
     
     
         20 . The receiver of  claim 19  wherein the receiver further comprises a vector adjuster arranged to adjust the transform vectors in response to the comparator so that the receiver transform vectors are modified to compensate for channel interference.  
     
     
         21 . The receiver of  claim 19  wherein the receiver further comprises a multiplier arranged to multiply an output of the gain block and the transform vectors.  
     
     
         22 . The receiver of  claim 21  wherein the multiplier produces multiplication results, and wherein the receiver further comprises a summer arranged to sum the multiplication results and the transform vectors in order to adjust the transform vectors.  
     
     
         23 . The receiver of  claim 22  further comprising a switch arranged to interconnect the vector transform and the vector adjuster during vector adjustment.  
     
     
         24 . The receiver of  claim 13  wherein the vector transform performs a matrix multiplication of the received signal and the receiver transform vectors.  
     
     
         25 . A receiver, wherein the receiver receives a signal from a channel, wherein C* designates the channel with interference, wherein the signal contains data, wherein the data has been processed by a transmitter transform so that the data is distributed in both time and frequency, wherein A designates the transmitter transform, wherein the receiver includes a receiver transform arranged to perform a transform on the received signal using a plurality of receiver transform vectors so as to recover the data even in the presence of a strong ghost, wherein T′ designates the receiver transform, wherein the receiver transform vectors are arranged so that the following equation is satisfied:  
       
         A×C*×T*=I  
       
       and wherein I is substantially the identity matrix.  
     
     
         26 . The receiver of  claim 25  wherein C designates the channel without channel interference, wherein T designates the receiver transform if channel interference is not present in the channel, wherein T′ designates the receiver transform if channel interference is present in the channel, and wherein the receiver transform satisfies the following equation with no channel interference:  
       
         A×C×T=I.  
       
     
     
         27 . The receiver of  claim 26  wherein C=I.  
     
     
         28 . The receiver of  claim 26  wherein the receiver comprises an adjuster, and wherein the adjuster is arranged to adjust the receiver transform vectors in response to the channel interference in order to produce the receiver transform T′.  
     
     
         29 . The receiver of  claim 28  wherein the adjuster comprises a comparator arranged to compare the transform to a reference.  
     
     
         30 . The receiver of  claim 29  wherein the reference is a known block of data stored in the receiver.  
     
     
         31 . The receiver of  claim 30  wherein the reference is stored in a transmitter and is used to form a training signal that is used by the vector adjuster to adjust the transform vectors.  
     
     
         32 . The receiver of  claim 29  wherein the comparator produces comparison results, and wherein the adjuster further comprises a gain block arranged to impose a fractional gain on the comparison results.  
     
     
         33 . The receiver of  claim 32  wherein the adjuster further comprises a multiplier arranged to multiply an output of the gain block and the receiver transform vectors.  
     
     
         34 . The receiver of  claim 33  wherein the multiplier produces multiplication results, and wherein the adjuster further comprises a summer arranged to sum the multiplication results and the receiver transform vectors in order to produce the receiver transform T′.  
     
     
         35 . The receiver of  claim 34  further comprising a switch arranged to interconnect the receiver transform and the adjuster during vector adjustment.  
     
     
         36 . The receiver of  claim 25  wherein the receiver transform performs a matrix multiplication of the received signal and the receiver transform vectors.  
     
     
         37 . The receiver of  claim 25  wherein C designates the channel without interference, wherein T designates the receiver transform without channel interference, and wherein T=A −1  when there is substantially no channel interference.  
     
     
         38 . A communication system including a transmitter and a receiver, wherein the transmitter includes a transmitter transform arranged to randomly distribute data to be transmitted in both time and frequency, wherein A designates the transmitter transform, wherein the transmitter is arranged to transmit a signal including the distributed data into a channel, wherein C* designates the channel with interference, wherein the receiver is arranged to receive the signal, wherein the receiver includes a receiver transform arranged to perform a transform on the received signal so as to recover the data even in the presence of a strong ghost, wherein T′ designates the receiver transform, wherein the receiver transform is arranged so that the following equation is satisfied:  
       
         A×C*×T*=I  
       
       and wherein I is substantially the identity matrix.  
     
     
         39 . The communication system of  claim 38  wherein C designates the channel without channel interference, wherein T designates the receiver transform without channel interference, wherein T′ designates the receiver transform with channel interference, and wherein the receiver satisfies the following equation with no channel interference:  
       
         A×C×T=I.  
       
     
     
         40 . The communication system of  claim 39  wherein C=I.  
     
     
         41 . The communication system of  claim 38  wherein the receiver transform performs a matrix multiplication of the received signal and the receiver transform vectors.  
     
     
         42 . A transmitter, wherein the transmitter includes a transmitter transform arranged to randomly distribute data to be transmitted in both time and frequency, wherein the transmitter is arranged to add a guard interval to the randomly distributed data, wherein the guard interval is known, is non-empty, and is non-related to the randomly distributed data, and wherein the transmitter is arranged to transmit the randomly distributed data and the guard interval.  
     
     
         43 . The transmitter of  claim 42  wherein the guard interval comprises components, and wherein the components are substantially equal.  
     
     
         44 . The transmitter of  claim 42  wherein the guard interval comprises essentially all zeros components.