Method and apparatus for radio frequency bandwidth sharing among heterogeneous radio communication system

• US 5,428,819 A
• Filed: 04/27/1993
• Issued: 06/27/1995
• Est. Priority Date: 04/27/1993
• Status: Expired due to Term

• Current Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Bernhardt, Richard C., D'Amico, Thomas V., Wang, Zhonghe
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): VO, NGUYEN THANH
• Application Number:
  US08/053,637
• Time in Patent Office: 791 Days
• Field of Search: 455/9, 455/33.1, 455/33.2, 455/33.3, 455/33.4, 455/34.1, 455/34.2, 455/58.1, 455/58.2, 455/62, 455/67.1, 455/63, 455/67.3, 379/59, 379/60, 375/95.1, 375/95.3
• US Class Current: 455/454
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

An etiquette controller (112) in a transmitter (14) in a first radio frequency (RF) communications system (10) enables radio frequency communications in a frequency bandwidth shared with heterogeneous RF communication systems (15). The etiquette controller (112) monitors the first RF signals in an isochronous frequency channel in a sub-band of the shared frequency bandwidth to determine whether (124) a frequency channel is free or whether (130, 136) the frequency channel comprises a communication channel which is free. In addition, the etiquette controller (112) causes the RF transceiver (102) to transmit (148) a channel relinquishment signal, monitors (150) the isochronous frequency channel for a predetermined monitoring time, and determines (152) whether the isochronous frequency channel is then free for the channel access.

Claims

1. A method for establishing communication etiquette amongst a plurality of radio frequency (RF) communication systems sharing a frequency bandwidth, the frequency bandwidth comprising a plurality of sub-bands including an isochronous frequency sub-band comprising a plurality of isochronous frequency channels, each isochronous frequency channel occupying a predetermined bandwidth and suitable for supporting communication between multiple RF communication systems on multiple communication channels, the method comprising the steps of:

assigning one of said isochronous frequency channels as a primary isochronous frequency channel for an RF communication system seeking to activate in the frequency bandwidth;

determining whether there is a free communication channel for the seeking RF communication system for assignment in any of the sub-bands;

if there is not a free communication channel for assignment in any isochronous frequency channel in the entire isochronous frequency sub-band, determining whether an RF communication system transmitting in a communication protocol which is interoperable with the seeking RF system is active in the primary isochronous frequency channel in said isochronous frequency sub-band; and

denying communication channel assignment to the seeking RF communication system if an RF communication system which is using a communication protocol that is interoperable with the seeking RF communication system is active in the primary isochronous frequency channel.

2. The method according to claim 1 further comprising the steps of:

transmitting a channel relinquishment signal in said primary isochronous frequency channel if it is determined that an RF communication system is active in said primary isochronous frequency channel which is using a communication protocol that is not interoperable with the seeking RF communication system to remove an RF communication using a non-interoperative communication protocol from the primary isochronous frequency channel;

monitoring a communication channel within the primary isochronous frequency channel for a predetermined monitoring time after the channel relinquishment signal is transmitted; and

determining whether a communication channel within the primary isochronous frequency channel is free for assignment in response to the issuance of the channel relinquishment signal.

3. The method according to claim 2 further comprising the step of assigning for communication by the seeking RF communication system a communication channel in the primary isochronous frequency channel if it is determined that a communication channel within the primary isochronous frequency channel is free for assignment.

4. The method according to claim 3 further comprising the step of denying assignment of a communication channel in the frequency bandwidth to the seeking RF communication system if it is determined that the communication channel is not free for the call assignment after expiration of the predetermined monitoring time.

5. An apparatus in a first radio frequency (RF) communications system for radio frequency communications in a frequency bandwidth shared with at least a second RF communication system, the frequency bandwidth comprising a plurality of sub-bands including an isochronous sub-band dedicated to isochronous communication systems the isochronous sub-band comprising a plurality of isochronous frequency channels each suitable for supporting communication between multiple RF communication systems on multiple communication channels, the apparatus comprising:

an RF transceiver for receiving first RF signals and for transmitting second RF signals;

a decoder coupled to the RF transceiver for determining whether the first RF signals are decodable as an interoperable transmitter signal transmitted by an RF communication system other than said first RF communication system and with which said first RF communication system is capable of interoperating;

a controller coupled to the decoder and the RF transceiver for controlling communication on an assigned communication channel; and

an etiquette controller coupled to the RF transceiver, decoder and controller for monitoring the first RF signals in a first isochronous frequency channel for determining whether the first isochronous frequency channel is free from use by other RF communication systems;

if the first isochronous frequency channel is determined to be free, assigning for use by the first RF communication system a communication channel in the first isochronous frequency channel;

if the first isochronous frequency channel is determined not to be free, determining whether the first RF communication system is interoperative with communication protocol signals transmitted by other RF communication systems in the first isochronous frequency channel and whether a communication channel is available in the first isochronous frequency channel; and

if it is determined that the first RF communication system is interoperative with communication protocol signals transmitted in the first isochronous frequency channel, assigning for use by the first RF communication system the communication channel determined to be available in the first isochronous frequency channel.

6. The apparatus of claim 5 wherein the etiquette controller assigns a free communication channel in an isochronous frequency channel different from the first isochronous frequency channel within the isochronous sub-band as the assigned communication channel to the first RF communication system if none of the communication channels within the first isochronous frequency channel are free and none of the isochronous frequency channels are occupied by other RF communication systems using communication signal protocols which are interoperable with the first RF communication system and have a free communication channel.

7. The apparatus of claim 6 wherein the etiquette controller assigns a free communication channel in a logical isochronous frequency channel in another of the plurality of sub-bands as the assigned communication channel to the first communication system if assignment of a free communication channel in the isochronous frequency channel different from the first isochronous frequency channel as the assigned communication channel to the first RF communication system cannot be made.

8. The apparatus of claim 7 wherein if the etiquette controller cannot make channel assignment to the logical isochronous frequency channel, the etiquette controller denies communication channel assignment to the first. RF communication system by the controller after the etiquette controller determines that an RF communication system which is using a communication protocol that is interoperable with the first RF communication system is active in the first isochronous frequency channel.

9. The apparatus of claim 8 wherein the etiquette controller provides a channel relinquishment signal to the RF transceiver for transmission therefrom in the first isochronous frequency channel to remove an RF communication using a communication protocol which is not interoperable with the first RF communication system from the first isochronous frequency channel, and wherein the etiquette controller monitors the first RF signals for a predetermined monitoring time to determine whether the first isochronous frequency channel is made free for assignment in response to the issuance of the channel relinquishment signal.

10. The apparatus of claim 9 wherein the etiquette controller assigns a free communication channel in the first isochronous frequency channel as the assigned communication channel if the etiquette controller determines that a communication channel is made free for assignment in response to the issuance of the channel relinquishment signal in the first iscochronous frequency channel.

11. The apparatus of claim 10 wherein the etiquette controller denies assignment of a communication channel in the frequency bandwidth if the etiquette controller determines that a communication channel in the first isochronous frequency channel is not free for assignment before the expiration of the predetermined monitoring time.

12. A method for establishing communication etiquette amongst a plurality of heterogeneous radio frequency (RF) communication systems sharing a frequency bandwidth, the frequency bandwidth comprising a plurality of sub-bands including at least one sub-band dedicated to isochronous communication systems which comprises a plurality of isochronous frequency channels, each isochronous frequency channel occupying a predetermined bandwidth and suitable for supporting communication between multiple RF communication systems on multiple communication channels, the method comprising steps of:

determining whether an RF communication system seeking to activate in the frequency bandwidth is isochronous or asynchronous;

if the seeking RF communication system is isochronous, determining whether a first isochronous frequency channel is free from use by other RF communication systems;

if the first isochronous frequency channel is determined to be free, assigning for use by the seeking RF communication system a communication channel in the first isochronous frequency channel;

if the first isochronous frequency channel is determined not to be free, determining whether the seeking RF communication system is interoperative with communication protocol signals used by other RF communication systems active in the first isochronous frequency channel and whether a communication channel is available in the first isochronous frequency channel; and

if it is determined that the seeking RF communication system is interoperative with communication protocol signals transmitted in the first isochronous frequency channel, activating the seeking RF communication system in the communication channel determined to be available in the first isochronous frequency channel.

13. The method of claim 12, and further comprising the step of assigning to each isochronous RF communication system which is to activate in the frequency bandwidth a primary isochronous frequency channel which is attempted prior to other isochronous frequency channels, and wherein the first isochronous frequency channel is the primary isochronous frequency channel.

14. The method of claim 13, and further comprising the step of assigning to each isochronous RF communication system which is to activate in the frequency bandwidth a secondary isochronous frequency channel which is monitored after it is determined that no communication channels in the primary isochronous frequency channel are free.

15. The method of claim 14, and further comprising the step of activating the seeking RF communication system in a communication channel determined to be free in the secondary isochronous frequency channel if it is determined that the seeking RF communication system is interoperable with a communication protocol used by an RF system active in the secondary frequency channel.

16. The method of claim 12, and further comprising steps of:

if there is not a free communication channel for assignment in any isochronous frequency channel in the entire isochronous frequency sub-band or in an isochronous frequency channel of a foreign sub-band, determining whether an RF communication system transmitting in a communication protocol which is interoperable with the seeking RF system is active in the first isochronous frequency channel in said isochronous frequency sub-band; and

denying assignment of a communication channel to the seeking RF communication system if an RF communication system which is using a communication protocol that is interoperable with the seeking RF communication system is active in said first isochronous frequency channel.

17. The method according to claim 16, and further comprising the steps of:

transmitting a channel relinquishment signal in said first isochronous frequency channel if it is determined that an RF communication system is active in said first isochronous frequency channel which is using a communication protocol that is not interoperable with the seeking RF communication system to remove the RF communication system using a non-interoperative communication protocol from the first isochronous frequency channel;

monitoring a communication channel within the first isochronous frequency channel for a predetermined monitoring time after the channel relinquishment signal is transmitted; and

determining whether a communication channel within the first isochronous frequency channel is free for assignment in response to the issuance of the channel relinquishment signal.

18. The method according to claim 17, and further comprising the step of assigning for communication by the seeking RF communication system a communication channel in the first isochronous frequency channel if the determining step determines a communication channel within the first isochronous frequency channel is free for assignment.

19. The method according to claim 18, and further comprising the step of denying assignment of a communication channel in the frequency bandwidth to the seeking RF communication system if the determining step determines that a communication channel is not free for the call assignment in the first isochronous frequency channel after the expiration of the predetermined monitoring time.

21. The method according to claim 12 further comprising the step of:

if none of the isochronous frequency channels are free and the seeking RF communication system is determined not to be interoperative with communication protocols of RF communication systems active in any of the isochronous frequency channels, or none of the frequency channels have a free communication channel, and all of the isochronous frequency channels in the isochronous frequency sub-band are busy, assigning for communication of the seeking RF communication system a free communication channel in a logical third isochronous frequency channel in another of the plurality of sub-bands.

20. In an RF communication system for operation on a frequency bandwidth shared by multiple heterogeneous RF communication systems, the frequency bandwidth comprising a plurality of sub-bands including an isochronous sub-band dedicated to isochronous communication systems, the isochronous sub-band comprising a plurality of isochronous frequency channels each suitable for supporting communication between multiple RF communication systems on multiple communication channels, each RF communications system comprising:

an RF transceiver for receiving RF signals and for transmitting RF signals;

a decoder coupled to the RF transceiver for determining whether received RF signals are decodable as an interoperable transmitter signal transmitted by another RF communication system other than said RF communication system;

a controller coupled to the decoder and the RF transceiver for controlling communication on an assigned communication channel; and

an etiquette controller coupled to the RF transceiver, the decoder and the controller for establishing the etiquette of said each RF communication system over the frequency bandwidth, said etiquette controller;

monitoring the RF signals in a first isochronous frequency channel for determining whether a first isochronous frequency channel is free from use by other RF communication systems;

if the first isochronous frequency channel is determined to be free, assigning for use by said each RF communication system a communication channel in the first isochronous frequency channel;

if the first isochronous frequency channel is determined not to be free, determining whether said each RF communication system is interoperative with communication protocol signals transmitted by other RF communication systems in the first isochronous frequency channel and whether a communication channel is available in the first isochronous frequency channel; and

if it is determined that said each RF communication system is interoperative with communication protocol signals transmitted in the first isochronous frequency channel, activating said each RF communication system in the communication channel determined to be available in the first isochronous frequency channel.