On-site/trunking system frequency sharing

• US 5,247,701 A
• Filed: 06/29/1990
• Issued: 09/21/1993
• Est. Priority Date: 06/29/1990
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Sobti, Arun, Hiben, Bradley M., Bocci, Paul M., McDonald, James A., Comroe, Richard A., Furtaw, Robert W.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): BELZER, CHRISTINE
• Application Number:
  US07/546,145
• Time in Patent Office: 1,180 Days
• Field of Search: 455/33, 455/34, 455/56, 379/59, 379/60, 379/63
• US Class Current: 455/520
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Shown, herein, is a method of allowing use of small, low-power communication systems within the service coverage area of larger trunked systems. The small, low-power systems are constructed to reuse at least some of the communication resources, also used by the larger system. The large system measures signal strength values of large cell communication units and transfers such values to the small systems. A small system compares the transferred values with a threshold and when the threshold is exceeded, reuses the communication resources under a TDM format within the small system.

Claims

1. A communication system within a service coverage area of a trunked communication system comprising:

A. the trunked communication system having;

i. a plurality of communications units;

ii. a plurality of communication resources, each resource having a frequency pair;

iii. at least one designated weak-signal resource of the plurality of communication resources;

iv. at least one base site;

v. means for allocating the plurality of communication resources;

vi. means for measuring a first signal quality factor of at least one transmitting communication unit

vii. means for comparing, the first signal quality factor on a control resource with a weak-signal threshold and when the weak-signal threshold exceeds the first signal quality factor, allocating the at least one weak-signal resource and,

viii. means for transferring the first signal quality factor to an at least one small-cell receiving means;

B. at least one small-cell communication system, wherein the small-cell communication system has;

i. a plurality of small-cell communication units;

ii. at least one small-cell base site;

iii. means for measuring a second signal quality factor of at least one transmitting communication unit;

iv. means for receiving the first signal quality factor from the trunked communication system;

v. means for comparing the first signal quality factor with a first threshold value and the second signal quality factor with a second threshold value to produce a first result and a second result, respectively; and

,

vi. means for allocating an available small-cell communication resource based, at least in part, upon the first result and the second result to an at least one requesting small-cell communication unit.

2. The communication system in claim 1 wherein the means for transferring the measured quality factor is through the use of land lines.

3. The communication system in claim 1 wherein the means for transferring the measured quality factor is through the use of an OSW transmitted by the trunked communication system to the at least one small-cell communication system.

4. A method of assigning communication resources within a first service coverage area, wherein the first service coverage area is at least partially coextensive with a second service coverage area that is serviced by a first communication system that makes use of a first set of communication resources, comprising the steps of:

A) measuring, at a base site, for the first communication system a first signal quality factor on a control resource of the first set of communication resources;

B) comparing the first signal quality factor with a weak-signal threshold;

C) allocating a weak-signal resource of the first set of communication resources when the weak-signal threshold at least equals the first signal quality factor on the control resource;

D) measuring, proximal to the first communication system, a first signal quality factor for at least one large system allocated resource of the first set of communication resources;

E) measuring, within the first service coverage area, a second signal quality factor of the same at least one large system allocated resource of the first set of communication resources;

F) comparing the first and second signal quality factors against at least one reference value, to obtain first and second comparison values, respectively;

G) when the first and second comparison values at least equal predetermined values, determining that the at least one of the first set of communication resources is available for allocation within the first service coverage area.

5. The method of claim 4, wherein the first set of communication resources includes a plurality of frequency pairs.

6. The method of claim 5, wherein at least some of the plurality of frequency pairs each include an inbound communication resource and an outbound communication resource.

7. A method of reusing communication resources, by an independent, small cell communication system within a service coverage area of a larger, large cell, trunked communication system, such method comprising the steps of:

comparing, by a small cell resource controller of the small cell system, an at least one large cell, signal quality factor of an operating frequency of an inbound large cell communication resource with a first threshold;

when the signal quality factor exceeds the first threshold, allocating, by the small cell resource controller, the frequency to a small cell communication unit;

measuring, by the small cell resource controller, the signal quality factors of communication resources allocated to small cell communication units;

comparing, by the small cell resource controller, the signal quality factors, measured by the small cell resource controller, against a second threshold; and

, deallocating communication resources from small cell communication units when the small cell measured signal quality factors exceeds the second threshold.

8. An apparatus for reusing communication resources, by an independent, small cell communication system within a service coverage area of a larger, large cell, trunked communication system, such apparatus comprising:

means for comparing, by a small cell resource controller of the small cell system, an at least one large cell, signal quality factor of an operating frequency of an inbound large cell communication resource with a first threshold;

when the signal quality factor exceeds the first threshold, allocating, by a means for allocating within the small cell resource controller, the frequency to a small cell communication unit;

means for measuring by the small cell resource controller, the signal quality factors of communication resources allocated to small cell communication units;

means for comparing, by the small cell resource controller, the signal quality factors, measured by the small cell resource controller, against a second threshold; and

, means for deallocating communication resources from small cell communication units when the small cell measured signal quality factors exceeds the second threshold.