ORTHOGONAL TIME FREQUENCY SPACE MODULATION OVER A PLURALITY OF NARROW BAND SUBCARRIERS
First Claim
1. A method of transmitting and receiving, on a per-frame basis, a plurality of data symbols over an impaired wireless channel comprising a plurality of narrow-band subcarriers, the method comprising:
- for each frame, using at least one processor to distribute the plurality of data symbols over a 2D OTFS delay-Doppler frame by assigning each data symbol to its own unique 2D OTFS delay-Doppler frame location;
OTFS transforming the data symbols on the 2D OTFS delay-Doppler frame by using each data symbol and frame location to modulate a unique, location specific, 2D basis wave function selected from a set of mutually orthogonal 2D basis wave functions operating over a 2D OTFS time-frequency frame, the transformation also spreading each data symbol, in a lossless and invertible manner, throughout substantially all of the 2D OTFS time-frequency frame, the transformation thereby creating a 2D OTFS time-frequency frame based wave aggregate;
further scrambling the 2D OTFS time-frequency frame based wave aggregate with a scrambling operation;
using a wireless transmitter to modulate and transmit portions of the scrambled 2D OTFS time-frequency frame based wave aggregate, over the plurality of narrow-band subcarriers, over a plurality of time intervals;
wherein a granularity and extent of the portions, the plurality of narrow-band subcarriers, and the time intervals are chosen so that the sum of the transmitted portions accurately characterize the scrambled 2D OTFS time-frequency frame based wave aggregate;
wherein the impaired wireless channel distorts the transmitted portions into channel distorted portions;
using a wireless receiver to receive and demodulate the channel distorted portions over the plurality of narrow-band subcarriers, over a plurality of time intervals, thereby recovering a channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate;
using an inverse of the scrambling operation to descramble the channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate, thereby creating a descrambled channel distorted replica of the 2D OTFS time-frequency based wave aggregate;
using at least one processor and an inverse of the OTFS transform to inverse transform the channel distorted replica of the 2D OTFS time-frequency frame based wave aggregate, thereby producing, once substantially all of the portions have been received, a channel distorted replica of the 2D OTFS delay-Doppler frame;
using a delay-Doppler 2D equalizer to correct the channel distorted replica of the 2D OTFS delay-Doppler frame, thereby producing a channel deconvoluted 2D OTFS delay-Doppler frame;
and extracting a plurality of replica data symbols from the channel deconvoluted 2D OTFS delay-Doppler frame.
2 Assignments
0 Petitions
Accused Products
Abstract
An Orthogonal Time Frequency Space Modulation (OTFS) modulation scheme that maps data symbols, along with optional pilot symbols, using a symplectic-like transformation such as a 2D Fourier transform and optional scrambling operation, into a complex wave aggregate and be backward compatible with legacy OFDM systems, is described. This wave aggregate may be processed for transmission by selecting portions of the aggregate according to various time and frequency intervals. The output from this process can be used to modulate transmitted waveforms according to various time intervals over a plurality of narrow-band subcarriers, often by using mutually orthogonal subcarrier “tones” or carrier frequencies. The entire wave aggregate may be transmitted over various time intervals. At the receiver, an inverse of this process can be used to both characterize the data channel and to correct the received signals for channel distortions, thus receiving a clear form of the original data symbols.
-
Citations
57 Claims
-
1. A method of transmitting and receiving, on a per-frame basis, a plurality of data symbols over an impaired wireless channel comprising a plurality of narrow-band subcarriers, the method comprising:
-
for each frame, using at least one processor to distribute the plurality of data symbols over a 2D OTFS delay-Doppler frame by assigning each data symbol to its own unique 2D OTFS delay-Doppler frame location; OTFS transforming the data symbols on the 2D OTFS delay-Doppler frame by using each data symbol and frame location to modulate a unique, location specific, 2D basis wave function selected from a set of mutually orthogonal 2D basis wave functions operating over a 2D OTFS time-frequency frame, the transformation also spreading each data symbol, in a lossless and invertible manner, throughout substantially all of the 2D OTFS time-frequency frame, the transformation thereby creating a 2D OTFS time-frequency frame based wave aggregate; further scrambling the 2D OTFS time-frequency frame based wave aggregate with a scrambling operation; using a wireless transmitter to modulate and transmit portions of the scrambled 2D OTFS time-frequency frame based wave aggregate, over the plurality of narrow-band subcarriers, over a plurality of time intervals; wherein a granularity and extent of the portions, the plurality of narrow-band subcarriers, and the time intervals are chosen so that the sum of the transmitted portions accurately characterize the scrambled 2D OTFS time-frequency frame based wave aggregate; wherein the impaired wireless channel distorts the transmitted portions into channel distorted portions; using a wireless receiver to receive and demodulate the channel distorted portions over the plurality of narrow-band subcarriers, over a plurality of time intervals, thereby recovering a channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate; using an inverse of the scrambling operation to descramble the channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate, thereby creating a descrambled channel distorted replica of the 2D OTFS time-frequency based wave aggregate; using at least one processor and an inverse of the OTFS transform to inverse transform the channel distorted replica of the 2D OTFS time-frequency frame based wave aggregate, thereby producing, once substantially all of the portions have been received, a channel distorted replica of the 2D OTFS delay-Doppler frame; using a delay-Doppler 2D equalizer to correct the channel distorted replica of the 2D OTFS delay-Doppler frame, thereby producing a channel deconvoluted 2D OTFS delay-Doppler frame; and extracting a plurality of replica data symbols from the channel deconvoluted 2D OTFS delay-Doppler frame. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 56)
-
-
22. A method of transmitting, on a per-frame basis, a plurality of data symbols over an impaired wireless channel comprising a plurality of narrow-band subcarriers, the method comprising:
-
for each frame, using at least one processor to distribute the plurality of data symbols over a 2D OTFS delay-Doppler frame by assigning each data symbol to its own unique 2D OTFS delay-Doppler frame location; OTFS transforming the data symbols on the 2D OTFS delay-Doppler frame by using each data symbol and frame location to modulate a unique, location specific, 2D basis wave function selected from a set of mutually orthogonal 2D basis wave functions operating over a 2D OTFS time-frequency frame, the transformation also spreading each data symbol, in a lossless and invertible manner, throughout substantially all of the 2D OTFS time-frequency frame, the transformation thereby creating a 2D OTFS time-frequency frame based wave aggregate; further scrambling the 2D OTFS time-frequency frame based wave aggregate with a scrambling operation; and using a wireless transmitter to modulate and transmit portions of the scrambled 2D OTFS time-frequency frame based wave aggregate, over the plurality of narrow-band subcarriers, over a plurality of time intervals; wherein a granularity and extent of the portions, the plurality of narrow-band subcarriers, and the time intervals are chosen so that the sum of the transmitted portions accurately characterize the scrambled 2D OTFS time-frequency frame based wave aggregate; wherein the impaired wireless channel distorts the transmitted portions into channel distorted portions. - View Dependent Claims (23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
-
-
40. A method of receiving, on a per-frame basis, a plurality of data symbols over an impaired wireless channel comprising a plurality of narrow-band subcarriers, wherein the impaired wireless channel distorts the transmitted portions into channel distorted portions;
- the method comprising;
using a wireless receiver to receive and demodulate the channel distorted portions over the plurality of narrow-band subcarriers, over a plurality of time intervals, thereby recovering a channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate; using an inverse of the scrambling operation to descramble the channel distorted replica of the scrambled 2D OTFS time-frequency frame based wave aggregate, thereby creating a descrambled channel distorted replica of the 2D OTFS time-frequency based wave aggregate; using at least one processor and an inverse of the OTFS transform to inverse transform the channel distorted replica of the 2D OTFS time-frequency frame based wave aggregate, thereby producing, once substantially all of the portions have been received, a channel distorted replica of the 2D OTFS delay-Doppler frame; using a delay-Doppler 2D equalizer to correct the channel distorted replica of the 2D OTFS delay-Doppler frame, thereby producing a channel deconvoluted 2D OTFS delay-Doppler frame; and extracting a plurality of replica data symbols from the channel deconvoluted 2D OTFS delay-Doppler frame. - View Dependent Claims (41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55)
- the method comprising;
-
57. A system, method or apparatus disclosed herein.
Specification