Performance through half-hopping and spatial diversity

• US 5,455,962 A
• Filed: 06/03/1994
• Issued: 10/03/1995
• Est. Priority Date: 09/19/1991
• Status: Expired due to Term

• Current Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Kotzin, Michael D.
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): SOBUTKA, PHILIP
• Application Number:
  US08/253,828
• Time in Patent Office: 487 Days
• Field of Search: 455/33.1, 455/33.2, 455/33.3, 455/50.1, 455/51.1, 455/56.1, 455/62, 455/54.1, 455/54.2, 455/52.1, 455/52.3, 455/13.3, 375/1, 375/202, 375/201, 370/95.3
• US Class Current: 455/422.1
• CPC Class Codes: H04B 7/061 using feedback from receiving side
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence

Abstract

A cellular communication system (50) is offered wherein communicated signals are exchanged on an indexed uplink communication resource and a non-indexed downlink communication resource. The non-indexed downlink communication format allows communication units to identify proximate service providers without knowledge of the index algorithm. The indexed signal transmitted by a user communication unit improves noise immunity in a signal transceived on the uplink. Signal quality is improved on the downlink through the use of selectable diversity antennas (22 or 23).

Claims

1. A cellular communication system comprising:

A) a plurality of base sites, each having a service coverage area and each having a primary channel and plurality of non-primary channels; and

B) a base site of the plurality of base sites and a communication unit located within the service coverage area of the base site having means for exchanging a communicated signal on a primary channel having a frequency hopped uplink and a non-frequency hopped downlink or a non-primary channel having a frequency hopped uplink and a frequency hopped downlink.

2. The system as in claim 1 wherein the means for exchanging communicated signals on the non-frequency hopping downlink further comprises a means for monitoring a downlink signal from an at least one other base site.

3. The system as in claim 2 wherein the means for monitoring a downlink signal from an at least one other base site further comprises means for measuring a signal quality factor of the monitored signal and means for detecting an ID of the monitored signal.

4. The cellular communication system of claim 1 further comprising:

C) means for transmitting, by the base site, the communicated signal within a TDM frame selectively through a designated antenna of a first and at least a second antenna located at the base site;

D) means for measuring, by the communication unit, signal quality factor information of the communicated signal from the designated antenna for the communicated signal; and

E) means for changing the designated antenna for the communicated signal, based, in part, upon said signal quality factor information.

5. The apparatus as in claim 4, wherein the means for changing the designated antenna further includes means for determining that the signal quality factor has exceeded a threshold.

6. The apparatus as in claim 4 wherein the signal quality factor information includes measuring signal strength.

7. The apparatus in claim 4 wherein the signal quality factor information includes measuring a bit error rate.

8. The system as in claim 4 further including means for receiving a resource allocation on a control resource from the base site.

9. The system as in claim 4 further including means for exchanging a communicated signal on the allocated resource between the communication unit and base site.

10. The system as in claim 4 wherein the means for changing the designated antenna includes means for comparing the measured signal quality factor with a threshold by the communication unit and upon occasion that the signal quality factor exceeds the threshold setting a bit on a next uplink transmission.

11. The system as in claim 4 further including means for communicating the signal quality factor of the designated antenna to the base site on the allocated resource.

12. The system as in claim 11 wherein the means for communicating include means for communicating the signal quality factor information on an indexed uplink.

17. The method of claim 4, wherein the base site includes a first and at least a second transmission antenna, further comprising the steps of:

C) transmitting, by the base site on the communication resource, a TDMA signal having a plurality of slots within a TDMA frame and with each slot of the TDMA signal transmitted through a designated antenna of the first and the at least a second transmission antenna located at the base site;

D) receiving the TDMA signal by the communication unit and measuring a signal quality factor; and

E) transmitting the measured signal quality factor from the communication unit to the base site for selecting an antenna of the first and the at least a second transmission antenna.

18. The method as in claim 17 further including the step of communicating a resource request on a control resource to the base site.

19. The method as in claim 18 further including the step of receiving a resource allocation on a control resource from the base site.

20. The method as in claim 19 further including the step of exchanging a communicated signal on the allocated resource between the communication unit and base site.

21. The method as in claim 20 further including the step of communicating an identity of the selected optimum antenna to the base site on the allocated resource.

13. A method of improving signal quality of a communicated signal exchanged within a cellular communication system between a base site and a communication unit, such method comprising the steps of:

A) transmitting, by the communication unit, a communicated signal to the base site on a frequency hopped uplink of a communication resource; and

B) receiving, by the communication unit, the communicated signal from the base site on either a non-frequency hopped downlink of the communication resource if the downlink is a primary radio channel or a frequency hopped downlink of the communication resource, if the downlink is a non-primary channel.

14. The method as in claim 13 further including the step of monitoring a downlink signal from an at least one other base site.

15. The method as in claim 14 further including the step of measuring a signal quality factor of the monitored signal and detecting an ID of the monitored signal.

16. The method as in claim 15 further including the step of communicating a measured signal quality factor to the base site.