Methods of operating and implementing wireless OTFS communciations systems

• US 9,634,719 B2
• Filed: 07/21/2015
• Issued: 04/25/2017
• Est. Priority Date: 05/28/2010
• Status: Active Grant

• Current Assignee: Cohere Technologies Inc
• Original Assignee: Cohere Technologies Inc
• Inventors: Rakib, Shlomo Selim, Hadani, Ronny
• Primary Examiner(s): Elliott, IV, Benjamin H
• Application Number:
  US14/805,400
• Publication Number:
  US 20150326273A1
• Time in Patent Office: 644 Days
• CPC Class Codes: H04B 1/692 Hybrid techniques using combinations of two or more spread spectrum techniques
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04L 25/0212 of impulse response
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 27/366 Arrangements for compensating undesirable properties of the transmission path between the modulator and the demodulator
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

Computerized wireless transmitter/receiver system that automatically uses combinations of various methods, including transmitting data symbols by weighing or modulating a family of time shifted and frequency shifted waveforms bursts, pilot symbol methods, error detection methods, MIMO methods, and other methods, to automatically determine the structure of a data channel, and automatically compensate for signal distortions caused by various structural aspects of the data channel, as well as changes in channel structure. Often the data channel is a two or three dimensional space in which various wireless transmitters, receivers and signal reflectors are moving. The invention'"'"'s modulation methods detect locations and speeds of various reflectors and other channel impairments. Error detection schemes, variation of modulation methods, and MIMO techniques further detect and compensate for impairments. The invention can automatically optimize its operational parameters, and produce a deterministic non-fading signal in environments in which other methods would likely degrade.

Claims

1. An automated method of wirelessly transmitting a plurality of symbols through a multi-dimensional data channel connecting at least one wireless transmitter and at least one wireless receiver;

said multi-dimensional data channel comprising at least two dimensions of space and one dimension of time;

said multi-dimensional data channel further comprising at least one wireless reflector, each said at least one wireless reflector comprising a reflector location, velocity, and at least one coefficient of wireless reflection;

each said at least one wireless transmitter comprising a wireless transmitter location and velocity;

each said at least one wireless receiver comprising a wireless receiver location and velocity;

said method comprising;

at least for said symbols that comprise data symbols, and where there are a plurality of such data symbols, using at least one processor to spread each data symbol throughout said plurality of data symbols in a lossless and invertible manner, thereby creating a plurality of OTFS symbols, and using said at least one transmitter and at least one processor to wirelessly transmit at least said data symbols as a plurality of OTFS symbols where each data symbol in said plurality of OTFS symbols is spread throughout a plurality of mutually orthogonal time shifted and frequency shifted wireless OTFS waveform bursts, thereby producing originally transmitted wireless OTFS waveform bursts;

wherein upon propagation through said multi-dimensional data channel, said originally transmitted wireless OTFS waveform bursts travel over at least one path, said at least one path, comprising at least one of;

a;

originally transmitted wireless OTFS waveform bursts traveling directly from said at least one wireless transmitter to said at least one wireless receiver as direct wireless OTFS waveform bursts; and

/or

b;

originally transmitted OTFS waveform bursts reflecting off of said at least one wireless reflector before reaching said at least one wireless receiver, thereby producing time delayed and Doppler frequency shifted reflected wireless OTFS waveform bursts at said at least one wireless receiver;

wherein at said at least one wireless receiver, the resulting combination of any said direct wireless OTFS waveform bursts and any said reflected wireless OTFS waveform bursts produces channel convoluted OTFS waveform bursts;

at said at least one wireless receiver, receiving said channel convoluted OTFS waveform bursts;

using at least one processor to determine channel response parameters of said multi-dimensional data channel between said at least one wireless transmitter and said at least one wireless receiver, wherein said channel response parameters of said multi-dimensional data channel are created by at least relative positions, relative velocities, and properties of said at least one wireless transmitter, said at least one wireless receiver, and said at least one wireless reflector;

using said channel response parameters and at least one processor to deconvolute received channel convoluted OTFS waveform bursts, thereby deriving at least an approximation of said originally transmitted OTFS waveform bursts;

using at least one processor to mathematically extract said plurality of data symbols from said approximation of said originally transmitted OTFS waveform bursts;

thereby transmitting at least some of said data symbols between said at least one wireless transmitter and at least one wireless receiver.

2. The method of claim 1, wherein a plurality of said symbols comprise data symbols;

wherein at least said data symbols are further arranged in symbol frames, said symbol frames being either N×

N or N×

M frames of said symbols, both N and M being integers greater than 1;

wherein, on a per symbol frame basis, said at least one processor spreads information from at least each data symbol across at least all data symbols in said symbol frame using a lossless and invertible transformation, thereby creating a corresponding OTFS frame comprising a plurality of OTFS symbols;

wherein said at least one wireless receiver receives said channel convoluted OTFS waveform bursts on a per OTFS frame basis, and extracts said plurality of OTFS symbols on a per OTFS frame basis, thereby creating an approximation of said OTFS frame;

further using said at least one processor and an inverse of said transformation to extract at least replica data symbols from said approximation of said OTFS frame.

3. The method of claim 1, further using said at least one transmitter and at least one processor to transmit at least one pilot symbol as at least one wireless pilot symbol waveform burst at at-least one defined time and frequency;

wherein the direct and reflected versions of said at least one wireless pilot symbol waveform burst reach said at least one wireless receiver as at least one channel convoluted pilot symbol waveform burst;

at said at least one wireless receiver, receiving said at least one channel convoluted pilot symbol waveform burst, and using at least one processor to determine the channel response parameters of said multi-dimensional data channel connecting said at least one wireless transmitter and at least one wireless receiver;

and subsequently using said channel response parameters to further deconvolute the received channel convoluted OTFS waveform bursts.

4. The method of claim 1, wherein at least some of said symbols or OTFS symbols comprise error detection or error correction symbols or OTFS symbols;

further using at least one processor at said at least one receiver to use said error detection or error correction symbols or OTFS symbols to detect when OTFS symbol transmission errors exceed a predetermined acceptable error level, and to automatically inform said receiver or said transmitter that said channel response parameters are suboptimum, and to initiate corrective action; and

/or

further using at least one processor and said at least one receiver to use said error detection or error correction symbols or OTFS symbols to automatically correct errors in other OTFS symbols or data symbols.

5. The method of claim 1, wherein said plurality of mutually orthogonal time shifted and frequency shifted wireless OTFS waveform bursts are further selected with regards to any of time latency, frequency bandwidth, or channel response parameter criteria, and wherein some OTFS symbols may be transmitted according to one selection criteria, while other OTFS symbols may be transmitted according to a different selection criteria.

6. The method of claim 1, wherein said plurality of mutually orthogonal time shifted and frequency shifted wireless OTFS waveform bursts are further characterized by:

1) burst time durations β

t that vary according to any of desired transmission latency time and/or spatial distributions of reflectors in said data channel; and

/or

2) burst frequency bandwidths δ

f that vary according to any of anticipated distribution of speeds and locations of receivers, transmitters, and reflectors in said data channel; and

/or

3) a number of OTFS data symbols transmitted per burst that vary according to both β

t and δ

f, said β

t and/or δ

f selected according to said channel response parameters, desired transmission latency time, and desired number of OTFS data symbols to be transmitted per burst.

7. The method of claim 1, wherein at least one of said wireless transmitter and said wireless receiver have multiple antennas, said multiple antennas positioned at different locations on or near said at least one wireless transmitter and said wireless receiver, and said multiple antennas sharing the same velocity of their respective wireless transmitter or wireless receiver;

further using said multiple antennas to perform at least one of further determining said channel response parameters and shaping at least a spatial distribution of said transmitted or received wireless waveform bursts.

8. The method of claim 1, wherein at least one of said wireless transmitter and said wireless receiver have multiple antennas, said multiple antennas positioned at different locations on or near said at least one wireless transmitter and said wireless receiver, and said multiple antennas sharing the same velocity of their respective wireless transmitter or wireless receiver;

wherein said multiple antennas are divided into at least a first subset of antennas and a second subset of antennas;

and said first subset of said multiple antennas transmits or receives a first set of wireless OTFS waveform bursts that differs from a second set of wireless OTFS waveform bursts transmitted or received by said second subset of antennas.

9. The method of claim 1, wherein at least one of said wireless transmitter and said wireless receiver are configured in a first full duplex device, and wherein at least one of said wireless transmitter and said wireless receiver are configured in a second full duplex device;

on at least said first full duplex device, further controlling coupling between said first full duplex device'"'"'s at least one wireless transmitter and said first full duplex device'"'"'s at least one wireless receiver so as to mitigate interference between said first full duplex device'"'"'s at least one wireless transmitter and said first full duplex device'"'"'s at least one wireless receiver while transmitting to said second full duplex device, and simultaneously also optimizing a sensitivity of said first full duplex device'"'"'s at least one wireless receiver while receiving from said second full duplex device'"'"'s at least one wireless transmitter;

wherein said controlling coupling is done by also obtaining self-channel response parameters of OTFS waveform bursts or pilot symbol waveform bursts traveling between said first full duplex device'"'"'s at least one wireless transmitter and said first full duplex device'"'"'s at least one wireless receiver; and

using said first full device'"'"'s at least one processor and said self-channel response parameters to digitally mitigate said interference.

10. The method of claim 1, wherein said at least one transmitter transmits polarized originally transmitted OTFS waveform bursts or pilot symbol waveform bursts according to at least one direction of polarization;

said at least one wireless reflector is a polarization altering wireless reflector that alters the polarization of said time delayed and Doppler frequency shifted reflected wireless OTFS waveform bursts or pilot symbol waveform bursts according to a first reflector polarization operator;

said at least one receiver is further configured to detect at least one direction of polarization in said received convoluted OTFS waveform bursts or pilot symbol waveform bursts;

wherein when said originally transmitted OTFS waveform bursts or pilot symbol waveform bursts reflect off of said at least one wireless reflector, at least some of said originally transmitted OTFS waveform bursts or pilot symbol waveform bursts are also polarization shifted according to said first reflector polarization operator;

further using said at least one direction of polarization in said received channel convoluted OTFS waveform bursts or pilot symbol waveform bursts to further determine the channel response parameters of said multi-dimensional data channel.

11. The method of claim 1 further creating a map database of the channel response parameters of said multi-dimensional data channel at a plurality of transmitter and receiver locations;

determining positions of said at least one wireless transmitter and said at least one wireless receiver;

and using positions of said at least one wireless transmitter and said at least one wireless receiver to search said map database and retrieve at least some channel response parameters of said multi-dimensional data channel at said positions of said at least one wireless transmitter and/or said at least one wireless receiver.

12. A method of operating at least one OTFS wireless transmitter device, each said at least one OTFS wireless transmitter device having a wireless transmitter device location and velocity, each said at least one OTFS wireless transmitter device configured to automatically wirelessly transmit a plurality of symbols through a multi-dimensional data channel to at least one wireless receiver device with a wireless receiver device location and velocity;

said multi-dimensional data channel comprising at least two dimensions of space and one dimension of time;

wherein said at least some of said plurality of symbols comprise a plurality of data symbols where transmission as a plurality of OTFS symbols by OTFS transmission is desired;

said multi-dimensional data channel further comprising at least one wireless reflector, each said at least one wireless reflector comprising a reflector location, velocity, and at least one coefficient of wireless reflection;

wherein channel response parameters of said multi-dimensional data channel are determined by at least relative positions, relative velocities, and said coefficients of wireless reflection of each said at least one OTFS wireless transmitter device, said at least one wireless receiver device, and said at least one wireless reflector;

each said at least one OTFS transmitter device comprising;

at least one processor, memory, at least one processor-controlled wireless transmitter component configured to transmit wireless signals at a plurality of frequencies, and at least one antenna;

said at least one processor, said memory, and at least one transmitter configured to spread at least said data symbols as OTFS symbols where each data symbol in said plurality of data symbols is spread throughout said plurality of data symbols in a lossless and invertible transformation creating OTFS symbols, and using said OTFS symbols to convert said plurality of data symbols into a plurality of mutually orthogonal time shifted and frequency shifted wireless OTFS waveform bursts; and

using said at least one antenna to wirelessly transmit said OTFS symbols as said plurality of mutually orthogonal time shifted and frequency shifted wireless OTFS waveform bursts, thereby producing originally transmitted wireless OTFS waveform bursts.

13. The method of claim 12, wherein said channel response parameters are at least initially determined by retrieving said channel response parameters from memory;

and

wherein said channel response parameters are subsequently at least partially determined based upon feedback obtained from an OTFS wireless receiver that has received said transmitted OTFS symbols.

14. A method of operating at least one OTFS wireless receiver device, each said at least one OTFS wireless receiver device having a wireless receiver device location and velocity, each said at least one OTFS wireless receiver device configured to automatically wirelessly receive a plurality of symbols transmitted through a multi-dimensional data channel by least one wireless transmitter device with a wireless transmitter device location and velocity;

wherein at least some of said plurality of symbols comprise a plurality of data symbols, each data symbol being previously spread over said plurality of data symbols by a lossless and invertible transformation, thus creating a plurality of OTFS symbols, where at least each data symbol encoded in said plurality of OTFS symbols was previously transmitted as a plurality of mutually orthogonal time shifted and frequency shifted originally transmitted wireless OTFS waveform bursts;

said multi-dimensional data channel comprising at least two dimensions of space and one dimension of time;

said multi-dimensional data channel further comprising at least one wireless reflector, each said at least one wireless reflector comprising a reflector location, velocity, and at least one coefficient of wireless reflection;

wherein upon propagation through said multi-dimensional data channel, said originally transmitted wireless OTFS waveform bursts travel over at least one path, said at least one path, comprising at least one of;

a;

originally transmitted wireless OTFS waveform bursts traveling directly from said at least one wireless transmitter to said at least one OTFS wireless receiver device as direct wireless OTFS waveform bursts; and

/or

b;

originally transmitted OTFS waveform bursts reflecting off of said at least one wireless reflector before reaching said at least one OTFS wireless receiver device, thereby producing time delayed and Doppler frequency shifted reflected wireless OTFS waveform bursts at said at least one OTFS wireless receiver device;

wherein at said at least one OTFS wireless receiver device, the resulting combination of any said direct wireless OTFS waveforms bursts and any said reflected wireless OTFS waveform bursts produces channel convoluted OTFS waveform bursts;

wherein channel response parameters of said multi-dimensional data channel are determined by at least relative positions, relative velocities, and properties of said at least one wireless transmitter device, said OTFS wireless receiver device, and said at least one wireless reflector;

said OTFS wireless receiver device comprising;

at least one processor-controlled wireless receiver component configured to receive wireless signals at a plurality of frequencies, at least one processor, memory, and at least one antenna;

said at least one processor configured to use said at least one wireless receiver component, at least one antenna, and memory to receive said convoluted OTFS waveform bursts or pilot symbol waveform bursts, and determine channel response parameters;

said at least one processor further configured to use said channel response parameters and said memory to deconvolute received channel convoluted OTFS waveform bursts, thereby deriving at least an approximation of said originally transmitted OTFS waveform bursts;

said at least one processor further configured to use said memory and an inverse of said transformation to mathematically extract said plurality of data symbols from said approximation of said originally transmitted OTFS waveform bursts, thereby receiving said plurality of data symbols.

15. The method of claim 14, wherein said channel response parameters are at least initially determined by retrieving said channel response parameters from memory;

and

further transmitting feedback pertaining to said channel response parameters to an OTFS transmitter that has transmitted said plurality of OTFS symbols.