Transmit gating in a wireless communication system

• US 6,545,989 B1
• Filed: 02/17/1999
• Issued: 04/08/2003
• Est. Priority Date: 02/19/1998
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Butler, Brian K.
• Primary Examiner(s): VINCENT, DAVID ROBERT
• Application Number:
  US09/251,981
• Time in Patent Office: 1,511 Days
• Field of Search: 370/277, 370/282, 370/310, 370/320, 370/321, 370/326, 370/328, 370/329, 370/335-337, 370/342, 370/347-348, 370/441, 370/442
• US Class Current: 370/329
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission
• CPC Class Codes: H04W 52/60 using different transmission rates for TPC commands
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]

Abstract

A method and system for communicating a frame of information according to both a continuous transmit format and a discontinuous transmit format. The present invention contemplates transmitting one or more data rates in either a continuous transmit mode (814) or a discontinuous transmit mode (812). The present invention contemplates continuous transmission only for certain data rates, and selection between continuous and discontinuous transmission for other data rates (810). Frames transmitted in the discontinuous transmit mode may be transmitted at a higher transmit power than in the continuous transmit mode (820). In one embodiment, the information is transmitted at a fifty-percent duty cycle during the second half of the frame when in the discontinuous transmit mode (808). During periods of non-transmission, an alternative system may be searched for as a possible candidate for hard handoff (816).

Claims

1. A method of transmitting a reverse link signal, the method comprising:

generating a first frame of data having a first data rate of a plurality of possible data rates;

selecting a discontinuous transmit mode based on the first data rate; and

transmitting the reverse link signal in the discontinuous transmit mode, wherein the reverse link signal comprises a pilot signal and a data signal, and wherein the data signal comprises the frame of data.

2. The method of claim 1 further comprising modulating the pilot signal and the data signal to provide the reverse link signal.

3. The method of claim 1 further comprising:

generating a second frame of data having a second data rate of the plurality of possible data rates; and

selecting a continuous transmit mode based on the second data rate.

4. The method of claim 1 wherein the first data rate is eighth-rate.

5. The method of claim 1 wherein the transmitting comprises transmitting the reverse link signal at a 50% duty cycle.

6. The method of claim 5 wherein the transmitting comprises transmitting the reverse link signal during a contiguous period representing half of a frame period.

7. The method of claim 5 wherein the transmitting comprises transmitting the reverse link signal during an earlier half of a 20 millisecond frame period.

8. The method of claim 5 wherein the transmitting comprises transmitting the reverse link signal during a latter half of a 20 millisecond frame period.

9. The method of claim 1 wherein the reverse link signal further comprises power control bits, and wherein the transmitting the reverse link signal in the discontinuous transmit mode results in a reduction in the update rate of the power control bits.

10. The method of claim 1 further comprising determining whether to transmit discontinuously, wherein the selecting is further based on the determining.

11. The method of claim 10 wherein the determining is based on a user-defined preference.

12. The method of claim 10 wherein the determining is based on a transmit power of a mobile station transmitter.

13. The method of claim 10 wherein the determining is based on a discontinuous mode message received from a base station.

14. A reverse link transmission apparatus comprising:

variable rate data source configured to generate a first frame of data having a first data rate of a plurality of possible data rates;

modulator configured to modulate a pilot signal and the first frame of data to provide a reverse link signal;

transmitter configured to transmit the reverse link signal, wherein the reverse link signal comprises a pilot signal and a data signal, and wherein the data signal comprises the frame of data; and

control processor configured to select a discontinuous transmit mode based on the first data rate and to control gating of the transmitter based on the selecting a discontinuous transmit mode.

15. The apparatus of claim 14 wherein the control processor is further configured to select a continuous transmit mode based on a second data rate of a frame generated by the variable rate data source, and to control gating of the transmitter based on the selecting a continuous transmit mode.

16. The apparatus of claim 14 wherein the control processor is further configured to select a discontinuous transmit mode when the first frame of data is an eighth-rate frame.

17. The apparatus of claim 14 wherein the control processor is configured to control gating of the transmitter in the discontinuous transmit mode at a 50% duty cycle.

18. The apparatus of claim 14 wherein the control processor is configured to control gating of the transmitter in the discontinuous transmit mode by enabling transmission during half of a frame period.

19. The apparatus of claim 14 wherein the control processor is configured to control gating of the transmitter in the discontinuous transmit mode by enabling transmission during an earlier half of a 20 millisecond frame period.

20. The apparatus of claim 14 wherein the control processor is configured to control gating of the transmitter in the discontinuous transmit mode by enabling transmission during a latter half of a 20 millisecond frame period.

21. The apparatus of claim 14 wherein the modulator is further configured to modulate power control bits to provide the reverse link signal, and wherein the transmitter is configured to transmit fewer power control bits per frame in the discontinuous transmit mode than in a continuous transmit mode.

22. The apparatus of claim 14 wherein the control processor is further configured to determine whether to transmit discontinuously and to base the selecting on the determining.

23. The apparatus of claim 22 wherein the control processor is configured to base the determining on a user-defined preference.

24. The apparatus of claim 22 wherein the control processor is configured to base the determining on a transmit power of a mobile station transmitter.

25. The apparatus of claim 22 wherein the control processor is configured to base the determining on a discontinuous mode message received from a base station.

26. A reverse link transmission apparatus comprising:

means for generating a first frame of data having a first data rate of a plurality of possible data rates;

means for selecting a discontinuous transmit mode based on the first data rate; and

means for transmitting a reverse link signal in the discontinuous transmit mode, wherein the reverse link signal comprises a pilot signal and a data signal, and wherein the data signal comprises the frame of data.