Sampling technique for digital beam former

• US 20020106041A1
• Filed: 10/05/2001
• Published: 08/08/2002
• Est. Priority Date: 02/05/2001
• Status: Active Grant

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Inventors: Chang, Donald C. D., Yung, Kar W., Von der Embse, Urban A.
• Granted Patent: US 7,068,733 B2
• Time in Patent Office: Days
• US Class Current: 375/347
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/2041 Spot beam multiple access
• CPC Class Codes: H04L 1/02 by diversity reception

Abstract

A mobile satellite payload 18 and a method for sampling communication signals 26 are provided. The mobile satellite payload 18 uses a plurality of receive radiating elements 24 within a phase array antenna 22 to convert the communication signals 26 to received signals [S(t)]. A plurality of low noise amplifiers (LNAs) 28 amplify the received signals [S(t)] to then be received by a plurality of analog-to-digital (A/D) converters 29. The A/D converters 29 transform the received signals [S(t)] into digital baseband signals [S″(t)].

Claims

1. A method of sampling communication signals within a mobile satellite payload having a phase array antenna, receive radiating elements, a plurality of low noise amplifiers (LNAs) and a plurality of analog-to-digital (A/D) converters, comprising:

receiving the communication signals with the receive radiating elements and forming received signals;

amplifying said received signals within the plurality of LNAs; and

transforming said received signals into digital baseband signals within the plurality of A/D converters.

2. A method as in claim 1 wherein transforming the received signals further comprises filtering the received signals within the plurality of A/D converters.

3. A method as in claim 1 wherein transforming said received signals comprises sampling the received signals at properly predetermined sampling rates.

4. A method as in claim 1 wherein transforming said received signals comprises maintaining the accuracy of said plurality of A/D converters aperture times (α

).

5. A method as in claim 1 wherein transforming said received signals further comprises sampling the received signals at a predetermined sampling frequency fs using an A/D converter with an aperture time of 1/A*fs.

6. A method as in claim 1 wherein transforming the received signals comprises sampling the received signals at frequencies selected from the following group:

SHF, KU, EHF, L-band, S-band, and C-band.

7. A method as in claim 1 wherein transforming said received signals comprises automatically filtering said received signals within the plurality of A/D converters.

8. A method as in claim 1 wherein transforming said received signals incorporates downconverting said received signals within the A/D converter.

9. A mobile satellite payload comprising:

a phase array antenna, wherein said phase array antenna comprises a plurality of receive radiating elements;

a plurality of low noise amplifiers (LNAs) electrically coupled to said receive radiating elements; and

a plurality of analog-to-digital (A/D) converters electrically coupled to said LNAs, wherein said plurality of A/D converters transform received signals into digital baseband signals.

10. A system as in claim 9 wherein said plurality of A/D converters incorporate the function of a downconverter.

11. A system as in claim 9 wherein said plurality of A/D converters incorporate the function of a filter.

12. A system as in claim 9 wherein said plurality of A/D converters operates with various aperture times.

13. A system as in claim 9 wherein said plurality of A/D converters are able to perform as low pass or band pass filters.

14. A system as in claim 9 wherein said plurality of A/D converters are able to sample at different predetermined sampling rates.

17. A method as in claim 16 wherein sampling said received signals comprises maintaining the accuracy of said plurality of A/D converters aperture times (α

).

18. A method as in claim 16 wherein sampling said received signals comprises sampling the received signals at properly predetermined sampling rates.

19. A method as in claim 16 wherein sampling the received signals further comprises sampling the received signals at a predetermined sampling frequency fs using an A/D converter with an aperture time of 1/A*fs.

15. A communication system comprising:

an antenna;

a low noise amplifier (LNA) electrically coupled to said antenna; and

an analog-to-digital (A/D) converter electrically coupled to said LNA, wherein said A/D converter transforms a received signal into a digital baseband signal.

16. A method of sampling communication signals within a mobile satellite payload having a phase array antenna, receive radiating elements, a plurality of low noise amplifiers (LNAs) and a plurality of analog-to-digital (A/D) converters, comprising:

receiving the communication signals through the use of the receive radiating elements and forming received signals;

amplifying said received signals within the plurality of LNAs;

downconverting said received signals within the plurality of A/D converters;

sampling said received signals within the plurality of A/D converters;

filtering said received signals within the plurality of A/D converters;

wherein the combination of downconverting, sampling, and filtering said received signals transforms said received signals into digital baseband signals.