Communication network

• US 8,005,422 B2
• Filed: 04/18/2008
• Issued: 08/23/2011
• Est. Priority Date: 03/17/2008
• Status: Expired due to Fees

• Current Assignee: Eutelsat, SA (Eutelsat Communications SA)
• Original Assignee: Eutelsat, SA (Eutelsat Communications SA)
• Inventors: Lance, Emmanuel, Fenech, Hector
• Primary Examiner(s): Le; Danh C
• Application Number:
  US12/148,347
• Publication Number:
  US 20090232046A1
• Time in Patent Office: 1,222 Days
• Field of Search: 455/12.1, 455/13.1, 455/13.2, 370/316
• US Class Current: 455/12.1
• CPC Class Codes: H04B 7/18532 Arrangements for managing transmission, i.e. for transporting data or a signalling message

Abstract

A telecommunication network for establishing radiofrequency links between gateways and ground terminals via a multispot satellite, the network comprising a multispot satellite, a plurality of gateways, each gateway establishing a link with the satellite on at least Ns link channels corresponding to Ns frequency intervals [f_i; f_i+1] with i varying from 0 to Ns−1 and a service area comprised of Nc cells each comprising a plurality of ground terminals, each cell being associated with a link spot beam with the satellite to which is allocated a frequency interval selected from among a plurality of frequency intervals [f′_i; f′_i+1] with i varying from 0 to N−1, N being an integer strictly greater than 1, is disclosed. The frequency f′₀ is substantially equal to the frequency f_Ns or the frequency f′_N is substantially equal to the frequency f₀. Each of the gateways is located in one of the Nc cells. The cells in which the gateways are located are associated with a spot beam to which is allocated a frequency interval selected from among the frequency intervals [f′_i; f′_i+1] with i varying from 1 to N−1 in the case where the frequency f′₀ is substantially equal to the frequency f_Ns or [f′_i; f′_i+1] with i varying from 0 to N−2 in the case where the frequency f′_N is substantially equal to the frequency f₀.

Claims

1. A telecommunication network for establishing radiofrequency links between gateways and ground terminals via a telecommunication satellite with several spot beams, designated as a multispot satellite, said network comprising:

a multispot satellite,

a plurality of gateways, each gateway establishing a link with said satellite on at least Ns link channels corresponding to Ns frequency intervals [f_i;

f_i+1] with i varying from 0 to Ns−

1 and,

a service area comprised of Nc cells each comprising a plurality of ground terminals, each cell being associated with a link spot beam with said satellite to which is allocated a frequency interval selected from among a plurality of frequency intervals [f′

_i;

f′

_i+1] with i varying from 0 to N−

1, N being an integer strictly greater than 1, frequency f′

₀ being substantially equal to frequency f_Ns, or frequency f′

_N being substantially equal to frequency f₀,

each of said gateways being located in one of said Nc cells, the cells in which said gateways are located are associated with a spot beam to which is allocated a frequency interval selected from among the frequency intervals;

[f′

_i;

f′

_i+1] with i varying from 1 to N−

1 in the case where frequency f′

₀ is substantially equal to frequency f_Ns, such that no gateway of said network is located in a cell associated with a spot beam to which frequency interval [f′

₀;

f′

₁] is allocated;

[f′

_i;

f′

_i+1] with i varying from 0 to N−

2 in the case where frequency f′

_N is substantially equal to frequency f₀, such that no gateway of said network is located in a cell associated with a spot beam to which frequency interval [f′

<sub>N−

1</sub>;

f′

_N] is allocated.

2. The network according to claim 1 wherein each gateway establishes a link with said satellite over 2×

Ns link channels, the 2×

Ns channels including;

Ns channels associated with a first polarization and corresponding to said Ns frequency intervals [f_i;

f_i+1] with i varying from 0 to Ns−

1 and,

Ns channels associated with a second polarization and corresponding to said Ns frequency intervals [f_i;

f_i+1] with i varying from 0 to Ns−

1, each cell being associated with a spot beam to which one of said first or second polarizations is allocated.

3. The network according to claim 1 wherein said frequency intervals belong to band Ka.

4. The network according to claim 1 wherein:

f′

₀=f_Ns+f_B with f_B having a positive value strictly less than the width of the guard band, or

the frequency f₀=f_N+f′

_B with f′

_B having a positive value strictly less than the width of the guard band.

5. The network according to claim 1 wherein the frequency f′

₀ is equal to the frequency f_Ns, or the frequency f′

_N is equal to the frequency f₀.

6. The network according to claim 5 wherein, in the case of uplinks, on the one hand between said gateways and said satellite and on the other hand between said cells and said satellite, the cells in which said gateways are located are associated with a spot beam to which is allocated the frequency interval [29.75 GHz;

30 GHz], each gateway of said network not being located in a cell associated with a spot beam to which is allocated the frequency interval [29.5 GHz;

29.75 GHz].

7. The network according to claim 5 wherein, in the case of downlinks, on the one hand between said gateways and said satellite and on the other hand between said cells and said satellite, the cells in which said gateways are located are associated with a spot beam to which is allocated the frequency interval [19.95 GHz;

20.2 GHz], no gateway of said network is located in a cell associated with a spot beam to which is allocated the frequency interval [19.7 GHz;

19.95 GHz].

8. The network according to claim 5 wherein cell is associated with one of the following four colors:

a first color corresponding in uplink to the frequency interval [29.5 GHz;

29.75 GHz] coupled to a first polarization and in downlink to the frequency interval [19.7 GHz;

19.95 GHz] coupled to a second polarization opposite from said first polarization;

a second color corresponding in uplink to the frequency interval [29.75 GHz;

30 GHz] coupled to said second polarization and in downlink to the frequency interval [19.95 GHz;

20.2 GHz] coupled to said first polarization;

a third color corresponding in uplink to the frequency interval [29.5 GHz;

29.75 GHz] coupled to said second polarization and in downlink to the frequency interval [19.7 GHz;

19.95 GHz] coupled to said first polarization;

a fourth color corresponding in uplink to the frequency interval [29.75 GHz;

30 GHz] coupled to said first polarization and in downlink to the frequency interval [19.95 GHz;

20.2 GHz] coupled to said second polarization;

the cells in which said gateways are located only being cells from said second or fourth color.

9. The network according to claim 8 wherein said first polarization is a right circular polarization and said second polarization is a left circular polarization.

10. The network according to claim 1 wherein the number Ns of channels is equal to eight.

11. The network according to claim 1 wherein the number Ns of channels is equal to five.

12. The network according to claim 1 wherein the integer N is equal to 2.