Granted Patent B2

US 12,621,190 · App. 17/808,447 · Granted May 5, 2026

Inventors: Peter John Black (La Jolla, CA); Jinghu Chen (San Diego, CA); Jing Jiang (San Diego, CA); Tamer Adel Kadous (San Diego, CA); Wanlun Zhao (San Diego, CA)

Assignee: Globalstar, Inc.

H04L25/0228H04L25/0212H04L25/022H04L25/0232H04L25/03834

Abstract

Claims (33)

1 . A system for Sounding Reference Signal channel estimation, the system comprising:

at least one antenna;

a frequency domain processing circuit configured to generate a de-covered frequency domain signal from a Sounding Reference Signal received by the at least one antenna using a base sequence, and to perform pulse shaping on the de-covered frequency domain signal to cause a direct current offset in the de-covered frequency domain signal to be reduced;

a time domain processing circuit having an input coupled to an output of the frequency domain processing circuit, the time domain processing circuit configured to suppress time domain channel impulse response leakage;

a second time domain processing circuit configured to rotate the Sounding Reference Signal on an indicator of a frequency offset, the second time domain processing circuit having an output coupled to an input of the frequency domain processing circuit; and

a channel estimation circuit configured to generate a channel estimate based on an output of the time domain processing circuit, wherein the channel estimate is associated with a wireless communication channel between a user equipment and a network node.

2 . The system of claim 1 , wherein the frequency domain processing circuit is configured to generate an estimated tone for an individual tone of the de-covered frequency domain signal based on at least two other tones of the de-covered frequency domain signal.

3 . The system of claim 2 , wherein the frequency domain processing circuit is configured to replace the individual tone with the estimated tone.

4 . The system of claim 2 , wherein the frequency domain processing circuit is configured to modify the individual tone based on the estimated tone.

5 . The system of claim 1 , wherein the frequency domain processing circuit is configured to perform pulse shaping using a raised cosine pulse.

6 . The system of claim 1 , wherein the network node is a base station.

7 . The system of claim 1 , wherein a base station comprises the channel estimation circuit.

8 . The system of claim 1 , wherein the frequency offset is associated with the user equipment.

9 . The system of claim 1 , further comprising a second frequency domain processing circuit configured to perform per-cyclic shift frequency domain processing, wherein the second frequency domain processing circuit is coupled between the time domain processing circuit and the channel estimation circuit.

10 . The system of claim 1 , wherein the time domain processing circuit comprises:

a filter comprising taps;

a noise power estimation circuit configured to estimate noise power for a sub-set of the taps of the filter corresponding to sub-carriers between channel impulse responses; and

a filter tap scaling circuit configured to perform a per-tap scaling on at least a portion of the taps of the filter based on the estimated noise power.

11 . The system of claim 1 , wherein the time domain processing circuit is configured to move a spur outside of time domain windows for cyclic shifts of the Sounding Reference signal.

12 . A system for Sounding Reference Signal channel estimation, the system comprising:

at least one antenna;

a frequency domain processing circuit configured to generate a de-covered frequency domain signal from a Sounding Reference Signal received by the at least one antenna using a base sequence, and to perform pulse shaping on the de-covered frequency domain signal to cause a direct current offset in the de-covered frequency domain signal to be reduced;

a time domain processing circuit having an input coupled to an output of the frequency domain processing circuit, the time domain processing circuit configured to suppress time domain channel impulse response leakage;

a second time domain processing circuit configured to pulse shape the Sounding Reference Signal with a raised cosine pulse, the second time domain processing circuit having an output coupled to an input of the frequency domain processing circuit; and

a channel estimation circuit configured to generate a channel estimate based on an output of the time domain processing circuit, wherein the channel estimate is associated with a wireless communication channel between a user equipment and a network node.

13 . The system of claim 12 , wherein the second time domain processing circuit is configured to rotate the Sounding Reference Signal on an indicator of a frequency offset.

14 . The system of claim 12 , wherein the frequency domain processing circuit is configured to generate an estimated tone for an individual tone of the de-covered frequency domain signal based on at least two other tones of the de-covered frequency domain signal.

15 . The system of claim 14 , wherein the frequency domain processing circuit is configured to replace the individual tone with the estimated tone.

16 . The system of claim 14 , wherein the frequency domain processing circuit is configured to modify the individual tone based on the estimated tone.

17 . The system of claim 12 , wherein the network node is a base station.

18 . The system of claim 12 , wherein a base station comprises the channel estimation circuit.

19 . The system of claim 12 , wherein the time domain processing circuit is configured to move a spur outside of time domain windows for cyclic shifts of the Sounding Reference signal.

20 . The system of claim 13 , wherein the frequency offset is associated with the user equipment.

Assignments (5)

Continuity (2)

References Cited (400)