Granted Patent B2

US 12,244,439 · App. 17/756,260 · Granted Mar 4, 2025

Inventors: Andreas Pfadler (Berlin, DE); Slawomir Stanczek (Berlin, DE); Peter Jung (Berlin, DE)

Assignee: FRAUNHOFER-GESELLSCHAFT ZUR FORDERUNG DER ANGEWANDTEN FORSCHUNG E.V.

H04L25/0224H04L5/0023H04L5/0051H04L27/2639H04L27/26532

Abstract

Claims (46)

1. An apparatus for a wireless transmitter device, the apparatus comprising:

a transmitter module configured to transmit wireless transmissions; and

a processing module configured to control the transmitter module,

wherein, the processing module is further configured to, prior to transmission of a wireless transmission:

generate one or more transmit symbols in a Delay-Doppler domain to obtain a Delay-Doppler representation,

transform the obtained Delay-Doppler representation into a Time-Frequency domain to obtain a Time-Frequency representation of the generated one or more transmit symbols, the Time-Frequency representation having a first frequency bandwidth and a first time duration,

spread the Time-Frequency representation having the first frequency bandwidth, the first duration in time, or both, to generate resources in the Time-Frequency representation for insertion of pilot symbols,

add pilot symbols to the spread Time-Frequency representation to obtain a Time-Frequency representation with a second frequency bandwidth or a second time duration, wherein the second frequency bandwidth and the second time duration are extended relative to the first frequency bandwidth and first time duration, respectively;

transform the Time-Frequency representation with the extended second frequency bandwidth or the extended time second duration to the time domain to obtain a time domain representation with the extended second frequency bandwidth or extended second time duration; and

transmit the time domain representation with the extended second frequency bandwidth or extended time second duration to a wireless receiver device for subsequent processing to obtain the Time-Frequency representation with the first frequency bandwidth and first time duration.

2. The apparatus of claim 1 , wherein the processing module is configured to use an accordion-shaped spread to spread the Time-Frequency representation having the first frequency bandwidth and the first time duration before adding the pilot symbols.

3. The apparatus of claim 1 , wherein the Time-Frequency representation having the first frequency bandwidth and the first time duration comprises a time-frequency grid, and wherein the processing module is further configured to extend the grid to open up grid points for adding the pilot symbols.

4. The apparatus of claim 1 , wherein the processing module is further configured to add a pilot grid to the Time-Frequency representation having the first frequency bandwidth and the first time duration, wherein spacings in the pilot grid are adapted to a coherence time of a wireless channel with reduced fast fading influence.

5. An access node of a wireless communication system comprising the apparatus of claim 1 .

6. An access node of a wireless communication system comprising the apparatus of claim 1 .

7. User equipment for a wireless communication system comprising the apparatus of claim 1 .

8. An apparatus for a wireless receiver device, the apparatus comprising:

a receiver module for receiving wireless transmissions; and

a processing module configured to control the receiver module, to receive a time domain representation of a signal from a wireless transmitter device,

wherein the processing module is further configured to:

transform the received time domain representation to a Time-Frequency representation, the Time-Frequency representation having an extended frequency bandwidth or an extended time duration,

de-spread the Time-Frequency representation having the extended frequency bandwidth, the extended duration in time, or both, to generate resources in the Time-Frequency representation with pilot symbols,

remove pilot symbols from the Time-Frequency representation to obtain a Time-Frequency representation with an unextended frequency bandwidth and an unextended time duration,

transform the Time-Frequency representation with the unextended frequency bandwidth or the unextended time duration into a Delay-Doppler domain to obtain a Delay-Doppler representation; and

determine estimated transmit symbols based on the Delay-Doppler representation.

9. The apparatus of claim 8 , wherein the processing module is further configured to estimate a wireless channel based on the pilot symbols and determine the estimated transmit symbols based on the estimated wireless channel.

10. The apparatus of claim 8 , wherein the processing module is further configured to perform compressed sensing of the wireless channel based on the pilot symbols.

11. The apparatus of claim 10 , wherein the processing module is further configured to perform the compressed sensing of the wireless channel based on the pilot symbols under the assumption that a representation of the wireless channel in the Delay-Doppler domain is sparse.

12. The apparatus of claim 8 , wherein the Time-Frequency representation having the extended frequency bandwidth or the extended time duration comprises a time-frequency grid, and wherein the processing module is further configured to delete the pilot symbols and pilot symbol grid points from the time-frequency grid to obtain the Time-Frequency representation with the unextended frequency bandwidth and the unextended time duration.

13. User equipment for a wireless communication system comprising the apparatus of claim 8 .

14. A method for a wireless transmitter device, the method comprising:

generating one or more transmit symbols in a Delay-Doppler domain to obtain a Delay-Doppler representation;

transforming the obtained Delay-Doppler representation into a Time-Frequency domain to obtain a Time-Frequency representation, the Time-Frequency representation having a first frequency bandwidth and a first time duration;

spreading the Time-Frequency representation having the first frequency bandwidth, the first duration in time, or both, to generate resources in the Time-Frequency representation for insertion of pilot symbols;

adding pilot symbols to the Time-Frequency representation to obtain a Time-Frequency representation with a second frequency bandwidth or a second time duration, wherein the second frequency bandwidth and the second time duration are extended relative to the first frequency bandwidth and first time duration, respectively;

transforming the Time-Frequency representation with the extended second frequency bandwidth or the extended second time duration to the time domain to obtain a time domain representation with the extended second frequency bandwidth or the extended second time duration; and

transmitting the time domain representation with the extended second frequency bandwidth or the extended second time duration to a wireless receiver device for subsequent processing to obtain the Time-Frequency representation with the first frequency bandwidth and the first time duration.

15. A non transitory computer readable medium including a computer program having a program code for performing at least one of the methods of claim 14 , when the computer program is executed on a computer, a processor, or a programmable hardware component.

16. A method for a wireless receiver device, the method comprising:

receiving a time domain representation of a receive signal from a wireless transmitter device;

transforming the received time domain representation to a Time-Frequency representation, the Time-Frequency representation having an extended frequency bandwidth or an extended time duration;

de-spreading the Time-Frequency representation having the extended frequency bandwidth, the extended duration in time, or both, to generate resources in the Time-Frequency representation with pilot symbols,

removing pilot symbols from the Time-Frequency representation to obtain a Time-Frequency representation with an unextended frequency bandwidth and an unextended time duration;

transforming the Time-Frequency representation with the unextended frequency bandwidth and the unextended time duration into a Delay-Doppler domain to obtain a Delay-Doppler representation; and

determining estimated transmit symbols based on the Delay-Doppler representation.

17. A non transitory computer readable medium including a computer program having a program code for performing at least one of the methods of claim 16 , when the computer program is executed on a computer, a processor, or a programmable hardware component.

Assignments (4)

Priority Claims (1)

Continuity (1)

References Cited (29)