Method and apparatus for signal combining in a high data rate communication system

• US 6,680,926 B2
• Filed: 11/19/2002
• Issued: 01/20/2004
• Est. Priority Date: 07/02/1999
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Grob, Matthew S., Bender, Paul E., Padovani, Roberto, Karmi, Gadi
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Jones, Prenell P
• Application Number:
  US10/300,391
• Publication Number:
  US 20030072287A1
• Time in Patent Office: 427 Days
• Field of Search: 370/331-338, 347/318, 347/316, 365/442, 365/458, 375/130, 375/211, 375/221, 455/13.4, 455/500, 455/10, 455/69
• US Class Current: 370/331
• CPC Class Codes: H04B 7/264 for data rate control
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff

Abstract

Reverse link busy bits are independently generated by each base station and indicate whether a base station has reached a reverse link capacity limit. A remote station combines multipath components of the reverse link busy bits in its Active Set and in response transmits a reverse link signal only when all of the reverse link busy bits indicate that the base stations in the Active Set have reverse link capacity. In one description, the remote station weights the reverse link busy signals in accordance with the signal strength of the transmitting base station and determines whether to transmit based on the weighted sum of the busy signals. In another description, the remote station weights the reverse link busy signals in accordance with the signal strength of the transmitting base station and determines a maximum reverse link data rate based on the weighted sum of the busy signals.

Claims

1. A base station, comprising:

a thirty-second Walsh spreading element that covers forward link traffic data in accordance with a Walsh code W_T;

a first Walsh spreading element that covers a FAC bit in accordance with a Walsh code W₁;

a seventeenth Walsh spreading element that covers a reverse link busy bit in accordance with a Walsh code W₁₇;

a set of twenty-nine Walsh spreading elements covers twenty-nine power control commands using Walsh codes W₂-W₁₆ and W₁₈-W₃₁, respectively;

a summer that sums the covered FAC bit, reverse link busy bit and twenty-nine power control commands and provides the sum to a multiplexer;

a multiplexer multiplexes the sum with the forward link traffic data.

2. The base station of claim 1, wherein the multiplexer is configured to insert into a slot the forward link traffic data and two pilot bursts with the second pilot burst having overhead bits on both sides of the second pilot burst.

3. The base station of claim 2, wherein the overhead bits inserted into the slot are the same.

4. The base station of claim 3, wherein the overhead bits are 64 Walsh chips in duration spread using thirty two bit Walsh codes providing four redundant versions of each piece of overhead information.

5. The base station of claim 3 further comprising a pseudonoise (PN) spreader configured to spread the data in the slot with a generated PN sequence, the generated PN sequence generated using a phase offset.

6. The base station of claim 5, wherein the data is transmitted in accordance with a QPSK modulation, wherein the in-phase and quadrature phase components are spread using two different pseudonoise sequences (PN_I and PN_Q).

7. The base station of claim 6, wherein the PN spread signal is provided to the transmitter that upconverts, amplifies and filters the PN spread signal for transmission through the duplexer and antenna.