US 5,809,060 A · High-data-rate wireless local-area network

An apparatus for communicating data between at least two data devices, the apparatus comprising:

(a) means for acquiring data from a data device;
(b) means for representing the data as a sequence of digital waveform symbols, the digital waveform symbols being selected from a set that includes more than two unique digital waveform symbols each digital waveform symbol being characterized by a symbol duration, wherein each of the unique digital waveform symbols is orthogonal with respect to each other unique digital waveform symbol in the set, and further wherein the means for representing the data as a sequence of digital waveform symbols includes:
(I) means for grouping the data into a sequence of groups of N bits each, each group representing a symbol selected from 2.sup.N possible data symbols;
and
(ii) data modulation means for representing each data symbol as a digital waveform symbol so as to form the sequence of digital waveform symbols;
(c) means for generating a direct-sequence spread spectrum encoding signal;
(d) multiplying means for combining the direct-sequence spread spectrum encoding signal with the sequence of digital waveform symbols to provide a transmit signal;
(e) modulator means for modulating a carrier signal in accordance with the transmit signal to provide a modulated signal;
and
(f) means for transmitting the modulated signal;
wherein said apparatus further includes (I) means for applying differential multiphase phase shift keying to each pair of sequentially neighboring waveform symbols so as to produce a waveform modulated by a combination of differential M-ary PSK and M-ary orthogonal function modulation;
and (ii) means for applying Reed-Solomon error correction coding to each waveform symbol, and means for applying binary error correction coding to the differential multiphase shift keying.

9 more elements

An apparatus for communicating data between at least two data devices, the apparatus comprising:

(a) means for acquiring data from a data device;
(b) means for representing the data as a sequence of digital waveform symbols, the digital waveform symbols being selected from a set that includes more than two unique digital waveform symbols, each digital waveform symbol being characterized by a symbol duration, wherein each of the unique digital waveform symbols is orthogonal with respect to each other unique digital waveform symbol in the set, and further wherein the means for representing the data as a sequence of digital waveform symbols includes:
(I) means for grouping the data into a sequence of groups of N bits each, each group representing a symbol selected from 2.sup.N possible data symbols;
and
(ii) data modulation means for representing each data symbol as a digital waveform symbol so as to form the sequence of digital waveform symbols;
(c) means for generating a direct-sequence spread spectrum encoding signal;
(d) multiplying means for combining the direct-sequence spread spectrum encoding signal with the sequence of digital waveform symbols to provide a transmit signal;
(e) modulator means for modulating a carrier signal in accordance with the transmit signal to provide a modulated signal;
and
(f) means for transmitting the modulated signal;
wherein the set of digital waveform symbols includes a set of Walsh-function waveforms, and said apparatus further includes means for applying Reed-Solomon error correction coding to each Walsh-function waveform.

8 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms;
and wherein the despreading/correlation means includes:
means for direct-sequence despreading of a DSSS encoded signal so as to provide a despread signal;
means for bandpass filtering the despread signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms;
means for splitting the filtered signal into an in-phase signal and a quadrature signal;
means for converting the in-phase signal and the quadrature signal respectively into a digital in-phase signal and a digital quadrature signal;
Walsh-function demodulator means for correlating the digital signals with the Walsh-function waveforms so as to provide correlated in-phase signals and correlated quadrature signals;
and
means for demodulating the correlated in-phase signals and the correlated quadrature signals so as to provide a plurality of envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of envelope signals so as to determine the largest magnitude envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude envelope signal so as to provide a binary data stream.

17 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the despreading/correlation means further includes means for providing a largest complex amplitude signal, the most-likely symbol means further includes means for providing a largest magnitude index signal, and the apparatus further comprises:
means, responsive to the largest complex amplitude signal and to the largest magnitude index signal, for binary DPSK demodulating the sequence of received symbols.

6 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms, and the despreading/correlation means includes:
means for bandpass filtering the incoming signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms with DSSS encoding;
means for splitting the filtered signal into an in-phase signal and a quadrature signal;
means for converting the in-phase signal and the quadrature signal respectively into an in-phase digital signal and a quadrature digital signal;
means for direct-sequence despreading each digital signal and correlating each digital signal with the Walsh-function waveforms so as to provide despread correlated in-phase signals and despread correlated quadrature signals;
and
means for demodulating the despread correlated in-phase signals and the despread correlated quadrature signals so as to provide a plurality of envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of envelope signals so as to determine the largest magnitude envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude envelope signal so as to provide a binary data stream.

15 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms, and wherein the despreading/correlation means includes:
a Walsh-function correlator, for receiving an input sample sequence, the correlator including a plurality of basic cells, each basic cell having an input and two outputs, the cells being interconnected to form a binary tree structure such that each possible path through the tree structure represents a unique function upon the input sequence, thereby providing a plurality of output sample sequences.

6 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms, and the despreading/correlation means includes:
means for pseudonoise despreading of a DSSS encoded signal so as to provide a despread signal;
means for bandpass filtering the despread signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms;
means for heterodyning to baseband the filtered signal with a coherent phase reference signal so as to provide an in-phase signal;
means for converting the in-phase signal into a digital in-phase signal;
Walsh-function demodulator means for correlating the digital signal with a set of Walsh-function waveforms so as to provide a plurality of correlated in-phase signals;
and
means for demodulating the correlated in-phase signals so as to provide a plurality of in-phase envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of in-phase envelope signals so as to determine the largest magnitude in-phase envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude envelope signal so as to provide a binary data stream.

16 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms, and the despreading/correlation means includes:
means for bandpass filtering the incoming signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms with DSSS encoding;
means for heterodyning to baseband the filtered signal with a coherent phase reference signal so as to provide an in-phase signal;
means for converting the in-phase signal into an in-phase digital signal;
means for direct-sequence despreading the digital signal and correlating the digital signal with a Walsh-function waveform so as to provide a despread Walsh in-phase signal;
and
means for envelope demodulating the despread Walsh in-phase signal so as to provide a plurality of envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of envelope signals so as to determine the largest magnitude envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude envelope signal so as to provide a binary data stream.

15 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the most-likely symbol means includes an M-way comparator having a plurality of two-way comparators interconnected as an inverted binary tree structure, each two-way comparator being adapted to provide an output amplitude that is the larger of two input amplitudes, and for providing an index of the larger of the two input amplitudes, the M-way comparator being adapted to provide an index indicating the largest of M input amplitudes, and to provide the largest amplitude of the M input amplitudes.

5 more elements

A method of receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible digital waveform symbols, wherein each digital waveform symbol in the set of possible digital waveform symbols is orthogonal with respect to each other digital waveform symbol in the set, and wherein the data are grouped into a sequence of groups of N bits each, each group representing a symbol from 2.sub.N possible data symbols, and each data symbol is represented as a digital waveform symbol so as to form the sequence of digital waveform symbols, the method comprising the steps of:

receiving the modulated signal to provide an incoming signal;
providing a timing signal;
removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal;
correlating the incoming signal with each possible orthogonal digital waveform symbol of a set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
converting the most-likely transmitted digital waveform symbol into a digital data sequence so as to provide a digital data stream;
and
providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms;
and the step of removing includes the steps of:
direct-sequence despreading of a DSSS encoded signal so as to provide a despread signal;
bandpass filtering the despread signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms;
splitting the filtered signal into an in-phase signal and a quadrature signal;
and
converting the in-phase signal and the quadrature signal respectively into a digital in-phase signal and a digital quadrature signal,
wherein the step of correlating includes the steps of:
correlating each digital signal with a Walsh-function waveform so as to provide a in-phase signal and a quadrature signal;
and
envelope demodulating the in-phase signal and the quadrature signal so as to provide a plurality of envelope signals,
wherein the step of receiving the plurality of despread correlation signals and determining therefrom a most-likely transmitted digital waveform symbol includes the steps of:
comparing each signal of the plurality of envelope signals so as to determine the largest magnitude envelope signal indicating a Walsh-function waveform most likely to have been transmitted;
and
providing a largest magnitude index signal indicative of the largest magnitude envelope signal,
and wherein the step of converting includes the step of:
decoding the largest magnitude envelope signal so as to provide a binary data stream.

22 more elements

A method of receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible digital waveform symbols, wherein each digital waveform symbol in the set of possible digital waveform symbols is orthogonal with respect to each other digital waveform symbol in the set, and wherein the data are grouped into a sequence of groups of N bits each, each group representing a symbol from 2.sub.N possible data symbols, and each data symbol is represented as a digital waveform symbol so as to form the sequence of digital waveform symbols, the method comprising the steps of:

receiving the modulated signal to provide an incoming signal;
providing a timing signal;
removing the pseudonoise direct-sequence spread spectrum encoding from the incoming signal;
correlating the incoming signal with each possible orthogonal digital waveform symbol of a set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
converting the most-likely transmitted digital waveform symbol into a digital data sequence so as to provide a digital data stream;
and
providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes Walsh-function waveforms;
and the step of removing includes the steps of:
bandpass filtering the incoming so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms with DSSS encoding;
splitting the filtered signal into an in-phase signal and a quadrature signal;
converting the in-phase signal and the quadrature signal respectively into a digital in-phase signal and a digital quadrature signal;
and
direct-sequence despreading each digital signal so as to provide a despread in-phase digital signal and a despread quadrature digital signal;
wherein the step of correlating includes the steps of:
correlating each digital signal with a Walsh-function waveform so as to provide a in-phase signal and a quadrature signal;
and
envelope demodulating the in-phase signal and the quadrature signal so as to provide a plurality of envelope signals,
wherein the step of receiving the plurality of despread correlation signals and determining therefrom a most-likely transmitted digital waveform symbol includes the steps of:
comparing each signal of the plurality of envelope signals so as to determine the largest magnitude envelope signal indicating a Walsh-function waveform most likely to have been transmitted;
and
providing a largest magnitude index signal indicative of the largest magnitude envelope signal,
and wherein the step of converting includes the step of:
decoding the largest magnitude envelope signal so as to provide a binary data stream.

22 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually-orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
despreading/correlation means, responsive to the timing signal and to the incoming signal, for both removing the direct-sequence spread spectrum encoding from the incoming signal, and for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of despread correlation signals;
most-likely symbol means for receiving the plurality of despread correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms, and the despreading/correlation means includes:
means for bandpass filtering the incoming signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms;
means for heterodyning to baseband the filtered signal with a coherent phase reference signal so as to provide an in-phase signal;
means for converting the in-phase signal into a digital in-phase signal;
means for despreading one of said incoming, filtered, in-phase and digital in-phase signals resulting in a despread digital in-phase signal following conversion of the in-phase signal into a digital in-phase signal;
Walsh-function demodulator means for correlating the despread digital in-phase signal with a set of Walsh-function waveforms so as to provide correlated in-phase signals;
and
means for demodulating the correlated in-phase signals so as to provide a plurality of in-phase envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of in-phase envelope signals so as to determine the largest magnitude in-phase envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude in-phase envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude in-phase envelope signal so as to provide a binary data stream.

16 more elements

Apparatus for receiving data communicated as a modulated signal between at least two data devices, the modulated signal being of the type encoded with direct-sequence spread spectrum encoding, and including digital waveform symbols selected from a set of possible mutually-orthogonal digital waveform symbols so that said data can be grouped into and conveyed as a sequence of groups of N bits each, the apparatus comprising:

means for receiving the modulated signal to provide an incoming signal;
means for providing a timing signal;
correlation means, responsive to the timing signal and to the incoming signal, for correlating the incoming signal with each possible digital waveform symbol of said set of possible digital waveform symbols so as to provide a plurality of correlation signals;
most-likely symbol means for receiving the plurality of correlation signals, and determining therefrom a most-likely transmitted digital waveform symbol so as to provide a sequence of received symbols;
means for converting the most-likely transmitted digital waveform symbol into a digital data bit sequence so as to provide a digital data stream;
and
means for providing the digital data stream to a data device;
wherein the set of possible digital waveform symbols includes a set of Walsh-function waveforms encoded with direct-sequence spread spectrum encoding, and the correlation means includes:
means for bandpass filtering the incoming signal so as to provide a filtered signal having a bandwidth substantially similar to the bandwidth of the set of Walsh-function waveforms;
means for heterodyning to baseband the filtered signal with a coherent phase reference signal so as to provide an in-phase signal;
means for converting the in-phase signal into a digital in-phase signal;
Walsh-function demodulator means for correlating the digital in-phase signal with a set of Walsh-function waveforms encoded with direct-sequence spread spectrum encoding so as to provide correlated in-phase signals;
and
means for demodulating the correlated in-phase signals so as to provide a plurality of in-phase envelope signals,
wherein the most-likely symbol means includes:
means for comparing each signal of the plurality of in-phase envelope signals so as to determine the largest magnitude in-phase envelope signal indicating a Walsh-function waveform most likely to have been transmitted, and for providing a largest magnitude index signal indicative of the largest magnitude in-phase envelope signal, and
wherein the means for converting includes:
data decoder means for decoding the largest magnitude in-phase envelope signal so as to provide a binary data stream.

15 more elements

High-data-rate wireless local-area network

Life of this patent

High-data-rate wireless local-area network

Life of this patent

Abstract

Claims57