Frequency hopping code division multiple access system and method

• US 6,507,600 B2
• Filed: 10/29/2001
• Issued: 01/14/2003
• Est. Priority Date: 02/17/1993
• Status: Expired due to Fees

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Schilling, Donald L.
• Primary Examiner(s): PHU, PHUONG M
• Application Number:
  US10/057,333
• Publication Number:
  US 20020106003A1
• Time in Patent Office: 442 Days
• Field of Search: 375/134, 375/132, 375/133, 375/137, 455/446, 455/561, 455/450, 455/452, 370/328, 370/329, 370/343, 342/358
• US Class Current: 375/134
• CPC Class Codes: H04B 1/7156 Arrangements for sequence synchronisation
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/2634 for channel frequency control
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• 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
• CPC Class Codes: H04W 16/30 Special cell shapes, e.g. doughnuts or ring cells
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

The present invention is a communication system and method having a base station for communication with multiple remote units. The system comprises a base station which utilizes a plurality of sets of frequencies for selectively communicating with remote units in a predefined coverage area. The coverage area is divided into N concentric regions, where each concentric region is assigned one of the plurality of frequency sets such that for any given concentric region a different frequency set is assigned than the frequency sets assigned to all other adjacent concentric regions. The base station includes a means for communicating data to a remote unit over the set of frequencies associated with the respective concentric region as the remote unit travels from one concentric region to another. The system also comprises at least one remote unit having means for communicating with the base station over the set of frequencies associated with the respective concentric region as the remote unit travels from one concentric region to another.

Claims

1. A communication system having a base station for communication with multiple remote units, the system comprising:

a base station utilizing a plurality of sets of frequencies for selectively communicating with remote units in a predefined coverage area, said coverage area divided into N concentric regions, each concentric region being assigned one of said plurality of frequency sets such that for any given concentric region a different frequency set is assigned than the frequency sets assigned to all other adjacent concentric regions;

said base station including means for communicating data to a remote unit over the set of frequencies associated with the respective concentric region as the remote unit travels from one concentric region to another; and

at least one remote unit having means for communicating with said base station over the set of frequencies associated with the respective concentric region as the remote unit travels from one concentric region to another.

2. A communication system according to claim 1 wherein each concentric region within the same area has a different assigned frequency set and N equals 6, whereby 6 regions are defined which use at least 6 different sets of frequencies.

3. A communication system according to claim 1 wherein said base station communicates with a plurality of remote units and said base station includes means for adjusting the size of each concentric region to maintain communications with only a selected maximum number of remote units in any one of said concentric regions.

4. A communication system according to claim 1 further comprising at least one additional base station, wherein each additional base station communicates with remote units in a different coverage area using said plurality of sets of frequency and portions of said different coverage areas which overlap or are adjacent to any of said concentric regions, utilize a set of frequencies different than the frequency set assigned to the respective concentric region.

5. A communication system according to claim 1 for overlaying an existing communication system wherein said plurality of frequency sets does not contain frequencies used by said existing communications system.

6. A communication system according to claim 5 wherein said existing communications system is a microwave system and said base station and remote unit include frequency hopping means for frequency hopping communication over said frequency sets in respective concentric regions.

7. A communication system according to claim 1 wherein said base station includes frequency hopping means comprising:

base modulator means for modulating said data as a modulated signal;

base hopping means for frequency hopping said modulated signal over the frequency set associated with a concentric region in which a remote unit is located;

base power means for amplifying said frequency hopped signal;

base antennae means for transmitting said frequency hopped signal; and

said remote unit includes frequency hopping means comprising;

a remote antenna for receiving said frequency hopped signal; and

remote receiver means for recovering said data from said received signal.

8. A communication system according to claim 1 wherein said base station determines the distance to said remote unit and determines which concentric region said remote unit resides based on said determination.

9. A base station for a communication system having at least one base station for communication with multiple remote units, the base station comprising:

means for utilizing a plurality of sets of frequencies for selectively communicating with remote units in a predefined coverage area, said coverage area divided into N concentric regions, each concentric region being assigned one of said plurality of frequency sets such that for any given concentric region a different frequency set is assigned than the frequency sets assigned to all other adjacent concentric regions; and

means for communicating data to a remote unit over the set of frequencies associates with the respective concentric region as the remote unit travels from one concentric region to another.

10. A base station according to claim 9 having a transmitter including:

modulator means for modulating data being communicated between the base station and remote units;

hopping means for frequency hopping said modulated data over the set of frequencies associated with a concentric region in which a remote unit is located; and

antennae means for transmitting said frequency hopped signal.

11. A base station according to claim 10 wherein the transmitter further comprises power means for amplifying said frequency hopped signal prior to transmission.

12. A base station according to claim 9 having a receiver including:

an antenna for receiving a frequency hopped signal communicated between the base station and a remote unit; and

receiver means responsive to the frequency set associated with a concentric region in which a remote unit is located for recovering data from said frequency hopped signal.

13. A base station according to claim 12 wherein said receiver means comprises:

a down converter for converting said frequency hopped signal to an intermediate frequency signal;

mixing means responsive to said frequency set associated with said remote unit'"'"'s concentric region to produce a mixed signal; and

demodulating means for recovering data from said mixed signal.

14. A base station according to claim 9 wherein each concentric region within the same area has a different assigned frequency set and N equals 6, whereby 6 concentric regions are defined which use at least 6 different sets of frequencies.

15. A communication method for communicating data between a base station and a remote unit, said base station having a predetermined coverage area, the method comprising the steps of:

dividing said coverage area into N concentric regions;

assigning each concentric region one of a plurality of sets of frequencies such that for any given concentric region a frequency set is assigned which is different than the frequency sets assigned to all other adjacent concentric regions; and

communicating with a remote unit over the set of frequencies associated with the respective concentric region as the remote unit travels from one concentric region to another.

16. A base station according to claim 15 for overlaying an existing communication system wherein said plurality of frequency sets does not contain frequencies used by said existing communications system.

17. A base station according to claim 16 wherein said existing communications system is microwave system.

18. The method according to claim 15 wherein each concentric region within the same area has a different assigned frequency set and, whereby N equals 6 whereby 6 concentric regions are defined which use at least 6 different sets of frequencies.

19. The method according to claim 15 further comprising:

determining the distance between said base station and a remote unit; and

determining which concentric region the remote unit resides based on said distance determination.