Cellular radiotelephone communications system

• US 5,073,971 A
• Filed: 09/05/1989
• Issued: 12/17/1991
• Est. Priority Date: 09/05/1989
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Schaeffer, Dennis R.
• Primary Examiner(s): KUNTZ, CURTIS A
• Application Number:
  US07/402,739
• Time in Patent Office: 833 Days
• Field of Search: 455/33, 455/34, 455/54, 455/56, 455/67, 455/69, 379/59, 379/60, 379/63, 370/95.1
• US Class Current: 455/447
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 16/12 Fixed resource partitioning
• CPC Class Codes: H04W 16/24 Cell structures

Abstract

A cellular radiotelephone communications system comprising a system of cells that are made up of an array of diretional sector antennas. These antennas are centrally located in the cell and radiates into a 60° area of the cell. Each antenna in a cell has a group of frequencies assigned to it that is different than the group of frequencies assigned to the other antennas within that cell. These frequency groups are repeated either 2 or 8 times respectively in a 4 or 16 cell repeat pattern, effectively forming a two cell reuse pattern. The preferred embodiment of this invention is asymmetrically positioning the repeating frequency groups in an alternating fashion so that one row faces in the opposite direction of another row. The asymmetrical positioning of cells is possible only by departing from the prior art, cellular positioning rules. The positioning rules used in this invention create a 4 or 16 cell repeat pattern by locating co-channel cells closer in one direction than another.

Claims

1. A cellular radiotelephone communications system having a plurality of cells, each cell having a plurality of frequencies, the plurality of cells being located substantially adjacent to each other in a first and a second direction, the system comprising:

a) at least one frequency, used in a narrow beam, directional manner, assigned to a first cell; and

b) uniform reuse of the at least one frequency in other cells that are located at a less distance in the first direction than in the second direction from the first cell.

2. The cellular radiotelephone communications system of claim 1 wherein the at least one frequency radiates into at least one 60°

sectors of the cell.

3. The cellular radiotelephone communications system of claim 1 wherein the at least one frequency is dynamically allocated between sectors of the cell.

4. The cellular radiotelephone communications system of claim 1 wherein each cell is assigned at least one predetermined group of frequencies.

5. The cellular radiotelephone communications system of claim 4 wherein reused frequencies radiate in a substantially same direction.

6. The cellular radiotelephone communications system of claim 4 wherein a first frequency of a first group of reused frequencies radiate in substantially opposite directions.

7. A cellular radiotelephone communications system having a plurality of cells, the plurality of cells being located substantially adjacent to each other in a first and a second direction, the system comprising:

a) at least one group of frequencies, each frequency of the group of frequencies used in a narrow beam, directional manner, assigned to a first cell;

b) uniform reuse of the at least one group of frequencies in other cells that are located at a less distance in the first direction than in the second direction from the first cell.

8. The cellular radiotelephone communications system of claim 7 wherein each frequency of the at least one group of frequencies radiates into at least one 60°

sector of the cell.

9. The cellular radiotelephone communications system of claim 7 wherein at least one frequency of the at least one group of frequencies is dynamically allocated between sectors of the cell.

10. The cellular radiotelephone communications system of claim 7 wherein reused frequencies radiate in a substantially same direction.

11. The cellular radiotelephone communications system of claim 7 wherein a first frequency of a first group of reused frequencies radiate in substantially opposite directions.

12. A cellular radiotelephone communications system having a plurality of cells, the plurality of cells being located substantially adjacent to each other in a first and a second direction, the system comprising:

a) a plurality of frequency groups, a first frequency of a first frequency group radiating into a 60°

sector of a first cell;

b) the first frequency of the first frequency group radiates in a substantially opposite direction from the first frequency of a second frequency group; and

c) uniform reuse of the first frequency group in other cells at a less distance in the first direction than in the second direction.

13. A cellular radiotelephone communications system having a plurality of cells, each cell having a plurality of frequencies, the plurality of cells being located substantially adjacent to each other in a first and a second direction, the system comprising:

a) at least one frequency, used in a narrow beam, directional manner, assigned to a first cell; and

b) non-interfering reuse of the at least one frequency asymmetrically about the first cell.

14. The cellular radiotelephone communications system of claim 13 wherein the at least one frequency radiates into at least one 60°

sector of the cell.

15. The cellular radiotelephone communications system of claim 13 wherein the at least one frequency is dynamically allocated between sectors of a cell.

16. The cellular radiotelephone communications system of claim 13 wherein each cell is assigned at least one predetermined group of frequencies.

17. The cellular radiotelephone communications system of claim 16 wherein reused frequencies radiate in a substantially same direction.

18. The cellular radiotelephone communications system of claim 16 wherein a first frequency of a first group of reused frequencies radiate in substantially opposite directions.

19. A method of allocating communications channels for a cellular radiotelephone communications system, the cellular radiotelephone communications system having a plurality of cells, each cell having a plurality of antennas centrally located in the cell with the antennas radiating into 60°

sectors of the cell, the method comprising the steps of;

a) providing different communications channels to each antenna of the plurality of antennas within a cell;

b) repeating the communications channels in different, asymmetrically located cells to increase the utilization of the communications channels.