Method of channel assignment by matching channel interference with channel link loss

• US 5,287,544 A
• Filed: 10/17/1991
• Issued: 02/15/1994
• Est. Priority Date: 10/17/1991
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Bonta, Jeffrey D., Menich, Barry J.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): FAILE, ANDREW I
• Application Number:
  US07/777,950
• Time in Patent Office: 852 Days
• Field of Search: 455/33.1, 455/33.2, 455/62-63, 455/67.3, 455/54.1, 455/54.2, 455/34.1, 455/34.2, 379/60, 379/59
• US Class Current: 455/450
• CPC Class Codes: H04W 36/20 for optimising the interference level
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method is offered of achieving a desired C/I ratio within a cellular system, at reduced transmitter power levels, by measuring a signal loss on a downlink between a base site transmitter (31) and mobile receiver (20) and calculating an uplink signal magnitude at a base site receiver. A communication channel is then selected from a number of communication channels based upon comparison of the uplink signal magnitude with pre-measured interference levels for each channel of the number of channels to produce a desired C/I ratio.

Claims

1. A method of achieving a desired C/I ratio within a cellular communication system, the method including the steps of:

A) grouping unallocated channels having more similar than dissimilar measured interference characteristics into a plurality of interference groups;

B) measuring a control signal on a downlink of a base site of the cellular communication system by a communication unit and communicating the measured signal value to the base site;

C) determining a calculated link signal loss by comparing the communicated measured signal value with a magnitude of the control signal transmitted by the base site; and

D) allocating a channel of the grouped unallocated channels to the communication unit based, at least in part, upon the calculated link signal loss and said interference groups to produce the desired C/I ratio.

2. The method as in claim 1 wherein the step of allocating a channel of the grouped unallocated channels to the communication unit further includes the step of determining a communicated signal level at the base site from the calculated link signal loss and a communication unit power setting.

3. The method as in claim 2 wherein the step of allocating a channel of the grouped unallocated channels to the communication unit further includes the step of selecting a channel from an interference group of the plurality of interference groups based upon the calculated link loss, the communication unit power setting and the desired C/I ratio.

4. An apparatus for achieving a desired C/I ratio within a cellular communication system, the apparatus comprising:

A) means for grouping unallocated channels having more similar than dissimilar measured interference characteristics into a plurality of interference groups;

B) means for measuring a control signal on a downlink of a base site of the cellular communication system by a communication unit and communicating the measured control signal value to the base site;

C) means for receiving the measured control signal value from the communication unit and determining a calculated link signal loss by comparing the measured control signal value with a communicated control signal value from a transmission site; and

D) means for allocating a channel of the grouped unallocated channels to the communication unit based, at least in part, upon the calculated link signal loss and said interference groups to produce the desired C/I ratio.

5. An apparatus for achieving a desired C/I ratio within a cellular communication system, the apparatus comprising:

A) means for grouping unallocated channels having more similar than dissimilar measured interference characteristics into a plurality of interference groups;

B) means for determining a communicated signal level at a base site from a calculated link loss and a communication unit power setting; and

C) means for allocating a channel of the grouped unallocated channels to a communication unit based, at least in part, upon the calculated link signal loss and said interference groups to produce the desired C/I ratio.

6. The apparatus as in claim 5 wherein the means for allocating a channel to a communication unit further comprises means for selecting the channel from an interference group of the plurality of interference groups to produce the desired C/I ratio.

7. A method for reducing interference within a cellular communication system, the method comprising the steps of:

A) grouping unallocated channels having more similar than dissimilar measured interference characteristics

B) measuring a downlink control signal to produce a measured signal value and communicating the measured signal value to the base site;

C) determining a calculated link signal loss by comparing the communicated measured signal value with a magnitude of the transmitted control signal; and

D) allocating a channel of the grouped unallocated channels to a communication unit based, at least in part, upon the calculated link signal loss and the interference grouping to produce a desired carrier to interference ratio.

8. A method for reducing interference within a cellular communication system, the method comprising the steps of:

A) grouping unallocated channels having more similar than dissimilar measured interference characteristics;

B) determining a communicated signal level at a base site from a calculated link loss and a communication unit power level and

C) allocating a channel of the grouped unallocated channels to a communication unit based, at least in part, upon the calculated link signal loss and the interference grouping to produce a desired carrier to interference ratio.

9. An apparatus for reducing interference within a cellular communication system, the apparatus comprising:

A) means for grouping unallocated channels having more similar than dissimilar measured interference characteristics to produce a plurality of interference groups;

B) means for measuring a downlink control signal and communicating the measured control signal value to a base site;

C) means for receiving the communicated measured control signal value from the communication unit and determining a calculated link signal loss by comparing the measured control signal value with a communicated control signal value from a transmission site; and

D) means for allocating a channel of the grouped unallocated channels to a communication unit based, at least in part, upon the calculated link signal loss and the interference grouping to produce a desired carrier to interference ratio at a relative minimum communication unit power level.

10. The apparatus as in claim 9 wherein the means for allocating a channel to a communication unit further comprises means for determining a communicated signal level at the base site from the calculated link loss and a communication unit power setting.

11. The apparatus as in claim 9 wherein the means for allocating a channel to a communication unit further comprises means for selecting the channel from an interference group of the plurality of interference groups to produce a desired C/I ratio.