Methods and systems for improving spectrum utilization for satellite communications

• US 10,404,354 B2
• Filed: 01/20/2017
• Issued: 09/03/2019
• Est. Priority Date: 02/27/2015
• Status: Active Grant

• Current Assignee: Asia Satellite Telecommunications Company Limited (Asia Satellite Telecommunications Holdings Ltd.)
• Original Assignee: Asia Satellite Telecommunications Company Limited (Asia Satellite Telecommunications Holdings Ltd.)
• Inventors: Tong, Roger Shun Hong, Vong, Fred Chun Yin, Hu, Hai, Leung, Harry Yin Chung, Chan, Man Hei, Yip, Kat Fan
• Primary Examiner(s): Chowdhury, Harun
• Application Number:
  US15/411,680
• Publication Number:
  US 20170135108A1
• Time in Patent Office: 956 Days
• Field of Search: 370316, 370343, 370480, 455 121, 455 302
• CPC Class Codes: H01Q 1/288 Satellite antennas
• CPC Class Codes: H04B 1/0057 using diplexing or multiplexing filters for selecting the desired band
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/18528 Satellite systems for providing two-way communications service to a network of fixed stations, i.e. fixed satellite service or very small aperture terminal [VSAT] system
• CPC Class Codes: H04B 7/18532 Arrangements for managing transmission, i.e. for transporting data or a signalling message
• CPC Class Codes: H04B 7/2041 Spot beam multiple access
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/27 between access points

Abstract

Satellite communication methods and payloads are described. An imbalance in uplink and downlink availability may be mitigated through digitizing uplink spectrum, extracting guard band channels, and grouping the guard band channels to create a composite channel. The composite channel is converted to analog and RF up-converted, amplified, and multiplexed with other downlink analog channels before being transmitted to Earth. The guard bands may be from the same band of spectrum or different bands of spectrum, such as C band, Ka band, Ku band, etc. A satellite payload is described with dual output multiplexers having partially overlapping channels and a dual feed configuration. In one downlink implementation, unused regional band spectrum may be dynamically allocated to a spot beam. In one uplink implementation, regional band spectrum may be shared by a spot beam using spatial separation of the regional uplink location from the spot beam coverage area and digital cancellation techniques.

Claims

1. A satellite payload for satellite communications, the payload comprising:

a regional beam antenna operable over a regional band of spectrum, wherein the regional band of spectrum includes a first frequency band and a first polarization;

a narrowband spot beam antenna operable over both (1) a spot beam band of spectrum having different frequencies from the regional band of spectrum, and (2) a portion of the regional band of spectrum wherein the portion includes the first frequency band and the first polarization;

a digital channelizer to route digitized spot beam channels to downlink channels, and wherein the digital channelizer is to dynamically assign one or more digitized spot beam channels to a part of the portion of the regional band of spectrum for downlink transmission by the narrowband spot beam antenna;

a digital-to-analog converter to convert the digitized spot beam channels to analog;

an RF up-converter to up-convert the analog spot beam channels; and

a spot beam spectrum amplifier to amplify the up-converted analog spot beam channels in the spot beam band of spectrum and the portion of the regional band of spectrum,

wherein spectrum includes both frequency and polarization.

2. The satellite payload of claim 1, further comprising a first diplexer to separate the amplified up-converted analog spot beam channels into the portion of the regional band of spectrum and the spot beam band, a first bandpass filter for the portion of the regional band of spectrum, a second bandpass filter for the spot beam band, and a second diplexer to combine filtered amplified up-converted analog spot beam channels for output to the narrowband spot beam antenna.

3. The satellite payload of claim 1, wherein the digital channelizer is to route digitized spot beam channels to the portion of the regional band of spectrum based upon excess demand in a coverage area for the spot beam and based on a determination that there is available capacity in the portion of the regional band of spectrum.

4. The satellite payload of claim 1, wherein the RF up-converter further up-converts regional beam channels in a remaining portion of the regional band of spectrum that excludes the portion of the regional band of spectrum, and further comprising a regional beam amplifier for amplifying the regional band of spectrum including the regional band channels and transmitting the amplified regional beam via the regional beam antenna.

5. The satellite payload of claim 1, wherein the digital channelizer is to assign said one or more digitized spot beam channels to said part of the portion of the regional band of spectrum based on a determination that the regional band of spectrum has excess capacity and that the capacity of the spot beam spectrum is fully engaged.

6. The satellite payload of claim 1, further comprising a plurality of narrowband spot beam antennas each operable over respective spot beam bands of spectrum different from each other, and each operable over the portion of the regional band of spectrum.

7. The satellite payload of claim 6, wherein the digital channelizer is to route at least one digitized spot beam channel from a first spot beam band of spectrum to a first channel in the portion of the regional band of spectrum, and to route at least one digitized spot beam channel from a second spot beam band of spectrum to a second channel in the portion of the regional band of spectrum.

8. The satellite payload claimed in claim 1, wherein the regional beam antenna is operable using left-hand circular polarization and right-hand circular polarization, and the narrowband spot beam antenna is operable using one of left-hand circular polarization and right-hand circular polarization.

9. The satellite payload claimed in claim 1, wherein both the regional beam antenna and the spot beam antenna are operable using the first polarization, and the first polarization is either left-hand circular polarization or right-hand circular polarization.

10. A method of dynamic spectrum reallocation in a satellite, the method comprising:

providing a regional beam antenna operable over a regional band of spectrum, wherein the regional band of spectrum includes a first frequency band and a first polarization, and wherein the regional beam antenna receives one or more regional beam channels;

providing a narrowband spot beam antenna operable over both (1) a spot beam band of spectrum having different frequencies from the regional band of spectrum, and (2) a portion of the regional band of spectrum wherein the portion includes the first frequency band and the first polarization, and wherein the spot beam antenna receives a plurality of spot beam channels;

digitally channelizing the plurality of spot beam channels to downlink channels, including dynamically assigning one or more digitized spot beam channels to a part of the portion of the regional band of spectrum;

converting the digitized spot beam channels to analog;

up-converting the analog spot beam channels;

amplifying the up-converted analog spot beam channels in the spot beam band of spectrum and the portion of the regional band of spectrum; and

transmitting the amplified spot beam band of spectrum and portion of the regional band of spectrum via the narrowband spot beam antenna,

wherein spectrum includes both frequency and polarization.

11. The method of claim 10, further comprising separating the amplified up-converted analog spot beam channels into the portion of the regional band of spectrum and the spot beam band, bandpass filtering the portion of the regional band of spectrum, bandpass filtering the spot beam band, and combining filtered amplified up-converted analog spot beam channels for output to the narrowband spot beam antenna.

12. The method claimed in claim 11, wherein the separating uses a first diplexer, and wherein the combining uses a second diplexer.

13. The method claimed in claim 10, further comprising determining available capacity in the portion of the regional band of spectrum, and routing the digitized spot beam channels to the portion of the regional band of spectrum based upon excess demand in a coverage area for the spot beam and the available capacity.

14. The method claimed in claim 10, wherein up-converting includes up-converting the regional beam channels in a remaining portion of the regional band of spectrum that excludes the portion of the regional band of spectrum, amplifying the regional band of spectrum including the regional band channels, and transmitting the amplified regional beam via the regional beam antenna.

15. The method claimed in claim 10, further comprising determining that the regional band of spectrum has excess capacity and that the capacity of the spot beam spectrum is fully engaged and, on that basis, assigning said one or more digitized spot beam channels to said part of the portion of the regional band of spectrum.

16. The method claimed in claim 10, wherein the satellite includes a plurality of narrowband spot beam antennas each operable over respective spot beam bands of spectrum different from each other, and each operable over the portion of the regional band of spectrum.

17. The method claimed in claim 16, further comprising routing at least one digitized spot beam channel from a first spot beam band of spectrum to a first channel in the portion of the regional band of spectrum, and routing at least one digitized spot beam channel from a second spot beam band of spectrum to a second channel in the portion of the regional band of spectrum.

18. The method claimed in claim 10, wherein the regional beam antenna is operable using left-hand circular polarization and right-hand circular polarization, and the narrowband spot beam antenna is operable using one of left-hand circular polarization and right-hand circular polarization.

19. The method claimed in claim 10, wherein both the regional beam antenna and the spot beam antenna are operable using the first polarization, and the first polarization is either left-hand circular polarization or right-hand circular polarization.

20. A satellite payload for satellite communications, the payload comprising:

a regional beam antenna operable over a regional band of spectrum;

a narrowband spot beam antenna operable over a spot beam band of spectrum and a portion of the regional band of spectrum;

a digital channelizer to route digitized spot beam channels to downlink channels, and wherein the digital channelizer is to dynamically assign one or more digitized spot beam channels to a part of the portion of the regional band of spectrum;

a digital-to-analog converter to convert the digitized spot beam channels to analog;

an RF up-converter to up-convert the analog spot beam channels;

a spot beam spectrum amplifier to amplify the up-converted analog spot beam channels in the spot beam band of spectrum and the portion of the regional band of spectrum;

a first diplexer to separate the amplified up-converted analog spot beam channels into the portion of the regional band of spectrum and the spot beam band;

a first bandpass filter for the portion of the regional band of spectrum;

a second bandpass filter for the spot beam band; and

a second diplexer to combine filtered amplified up-converted analog spot beam channels for output to the narrowband spot beam antenna.