DYNAMIC PROGRAM CONTROL FOR CHANNEL ASSIGNMENT IN MOBILE COMMUNICATION SYSTEMS

• US 3,764,915 A
• Filed: 06/25/1971
• Issued: 10/09/1973
• Est. Priority Date: 06/25/1971
• Status: Expired due to Term

• Current Assignee: Donald Clyde Cox, Douglas Otto John Reudink
• Original Assignee: Donald Clyde Cox, Douglas Otto John Reudink
• Inventors: Cox, Donald Clyde, Reudink, Douglas Otto John
• Primary Examiner(s): Atkinson, Charles E.
• Application Number:
  US05/156,791
• Time in Patent Office: 837 Days
• Field of Search: 325/51,53,55 340/146.1C,47 179/41A
• US Class Current: 455/452.1
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network

Abstract

To determine a channel which may be advantageously assigned to a mobile user via a preferred one of a plurality of spacially remote base stations, a central control computer considers the status of use of all communication channels utilized by the system. All of these channels constitute but a single set, so any of them may be assigned to a mobile user by way of any base station. Thus, the allocation procedures utilized by the computer feature optimization tests which insure minimal station-tostation interference with optimal '"'"''"'"''"'"''"'"'packing'"'"''"'"''"'"''"'"' and re-use of the channels over the entire system.

Claims

1. In a mobile communication system including a central control and a plurality of local base stations, an improved method for dynamically assigning one of a plurality of transmission channels wherein the improvement comprises:

searching said local base stations for status of use of all of said transmission channels;

identifying for each of said transmission channels a set of local base stations at which the channel is in use;

selecting the ones of said channels whose associated set from said identifying step includes only base stations which are located at least a predetermined distance from the preferred base station;

choosing from said ones of said channels in accordance with optimization criteria a preferred channel for assignment; and

assigning the preferred channel.

2. The method described in claim 1 wherein said predetermined distance in said selecting step is the distance at which signals transmitted by two base stations will interfere with one another.

3. The method of claim 1 wherein the step of choosing from said ones of said channels a preferred channel for assignment comprises identifying a channel whose associated set from said identifying step includes a base station which is separated from said preferred base station by a distance closest to said predetermined distance.

4. The method of claim 1 wherein the step of choosing from said ones of said channels a preferred channel for assignment comprises identifying a channel whose associated set from said first identifying step includes a base station which is separated from said preferred base station by a distance closest to said predetermined distance plus an additional distance to facilitate packing control.

5. The method of claim 1 wherein the step of choosing from said ones of said channels a preferred channel for assignment comprises calculating once for each channel the sum of the squares of the distance between the preferred base station and each local base station using the channel, and picking the channel characterized by the minimum sum of the squares of said calculating step.

6. In a mobile radio-telephone system including a central control and a plurality of local base stations, a method for dynamically assigning one of a plurality of transmission channels to a mobile user via a preferred base station comprising the steps of:

selecting a preferred base station from which communication on the assigned channel will be transmitted and received;

choosing a first one of said plurality of transmission channels;

searching said plurality of base stations for usage thereby of said first channel;

comparing the spacial relationship of said preferred base station with a base station using said first channel in accordance with re-use criteria;

repeating said choosing, searching, and comparing steps for each of said plurality of channels; and

selecting in accordance with optimization criteria a preferred channel from the set of channels used by the base stations satisfying the re-use criteria.

7. The method for assigning transmission channels described in claim 6 wherein said searching step includes the steps of iteratively searching sets of base stations, each set comprising a portion of said plurality of base stations located approximately equisdistant from said preferred base station, nearer base stations being searched prior to more distant base stations.