Method for reducing co-channel of cross-polarization interference in a satellite data communication system by offsetting channel frequencies
First Claim
1. A method for assigning communication frequency channels to users of a FDMA communications system employing an available bandwidth, said method comprising:
- (a) partitioning said available bandwidth into a first set of sub-bands, said first set comprising several sub-bands each having a sub-band bandwidth;
(b) partitioning said available bandwidth into a second set of sub-bands, said second set comprising several sub-bands each having said sub-band bandwidth, the sub-bands of said second set corresponding to the sub-bands of the first set and being offset in frequency from the corresponding sub-bands of the first set by a predetermined frequency offset, the predetermined frequency offset being less than said sub-band bandwidth, whereby corresponding sub-bands of the first and second sets overlap in frequency but do not have identical frequency ranges; and
(c) assigning some of the users a communication frequency channel within said first set of sub-bands and assigning others of said users a communication frequency channel within said second set of sub-bands, wherein said assigning the communication frequency channels is done in a periodic pattern to lessen the number of nearby users that are assigned a frequency channel within the same sub-band of the same subset.
5 Assignments
0 Petitions
Accused Products
Abstract
A method for reducing co-channel or cross-channel interference between cells of a cell network in a frequency division multiple access (FDMA) communications system is disclosed. The method comprises the steps of: dividing the cells of the cell network into a first subset of cells and a second subset of cells; dividing the available bandwidth for the system into a first set of sub-bands, each of which has a sub-band bandwidth and a second set of sub-bands, each of which has a sub-band bandwidth, the second set of sub-bands being offset in frequency from the first set of sub-bands; assigning the first set of sub-bands to the first subset of cells and the second set of sub-bands to the second subset of cells.
-
Citations
19 Claims
-
1. A method for assigning communication frequency channels to users of a FDMA communications system employing an available bandwidth, said method comprising:
-
(a) partitioning said available bandwidth into a first set of sub-bands, said first set comprising several sub-bands each having a sub-band bandwidth; (b) partitioning said available bandwidth into a second set of sub-bands, said second set comprising several sub-bands each having said sub-band bandwidth, the sub-bands of said second set corresponding to the sub-bands of the first set and being offset in frequency from the corresponding sub-bands of the first set by a predetermined frequency offset, the predetermined frequency offset being less than said sub-band bandwidth, whereby corresponding sub-bands of the first and second sets overlap in frequency but do not have identical frequency ranges; and (c) assigning some of the users a communication frequency channel within said first set of sub-bands and assigning others of said users a communication frequency channel within said second set of sub-bands, wherein said assigning the communication frequency channels is done in a periodic pattern to lessen the number of nearby users that are assigned a frequency channel within the same sub-band of the same subset. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method for reducing interference between cells of a cell network using an FDMA communications system employing an available bandwidth, said method comprising the steps of:
-
(a) dividing said cells of said cell network into a first subset of cells and a second subset of cells; (b) partitioning said available bandwidth into a first set of sub-bands each having a sub-band bandwidth; (c) partitioning said available bandwidth into a second set of sub-bands each having said sub-band bandwidth, the sub-bands of said second set corresponding to the sub-bands of the first set and being offset in frequency from the corresponding sub-bands of the first set by a predetermined frequency offset, the predetermined frequency offset being less than said sub-band bandwidth, whereby corresponding sub-bands of the first and second sets overlap in frequency but do not have identical frequency ranges; (d) assigning said first set of sub-bands to said first subset of cells; and (e) assigning said second set of sub-bands to said second subset of cells. - View Dependent Claims (7, 8, 9, 10, 11, 12)
-
-
13. An FDMA communications system having reduced interference, said FDMA communications system operating over a cell network including a plurality of cells having transmitters capable of transmitting on communication frequency channels, said FDMA communications system employing an available bandwidth, said FDMA communications system comprising:
-
a first subset of cells, said first subset of cells being selected from said plurality of cells, said first subset of cells being assigned a first set of sub-bands each having sub-band bandwidth, said first set of sub-bands being formed from a partitioning of said available bandwidth; and a second subset of cells, said second subset of cells being selected from said plurality of cells, said second subset of cells being assigned a second set of sub-bands each having said sub-band bandwidth, said second set of sub-bands being formed from a partitioning of said available bandwidth, said second set of sub-bands corresponding to the sub-bands of the first set and being offset in frequency from the corresponding sub-bands of the first set by a predetermined frequency offset, the predetermined frequency offset being less than said sub-band bandwidth, whereby corresponding sub-bands of the first and second sets overlap in frequency but do not have identical frequency ranges. - View Dependent Claims (14, 15, 16, 17, 18, 19)
-
Specification