Enhanced access in wireless communication systems under rapidly fluctuating fading conditions

• US 6,507,568 B2
• Filed: 08/27/1997
• Issued: 01/14/2003
• Est. Priority Date: 08/27/1997
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Rege, Kiran M., Kuo, Wen-Yi, Kumar, Sarath
• Primary Examiner(s): RAO, SEEMA SRINIVAS
• Application Number:
  US08/918,996
• Publication Number:
  US 20010043578A1
• Time in Patent Office: 1,966 Days
• Field of Search: 370/335, 370/342, 370/331, 370/332, 370/334, 370/252, 370/441, 370/329, 455/436, 455/442, 455/524, 455/525, 375/347, 375/349, 375/267, 375/148
• US Class Current: 370/329
• CPC Class Codes: H04B 1/7115 Constructive combining of multi-path signals, i.e. RAKE receivers
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04

Abstract

A mobile communications system employs extended channel assignment messaging during the call setup portion of a mobile call. As part of the call setup process, a mobile station sends an access request message to a primary base station that includes a list of alternate base stations. As call setup continues, the mobile station employs diversity reception in monitoring the paging channel of three base stations, each selected as a function of the strength of the signal-to-noise ratios of their respective pilot tones.

Claims

1. A method for use in a wireless mobile station of a wireless communication system during an access state of the wireless communication system, the method comprising the steps of:

transmitting a message to at least one wireless base station of the wireless communication system, the message representative of a call setup state of operation;

demodulating different received signals from a plurality of wireless base stations of the wireless communication system representing a first reply channel, associated with a first wireless base station, and a second reply channel, associated with a second wireless base station, to provide a respective first demodulated signal and a second demodulated signal;

decoding the first demodulated signal to provide a first message;

decoding the second demodulated signal to provide a second message, wherein the decoding of the first demodulated signal is independent of the decoding of the second demodulated signal; and

selecting one of the plurality of decoded messages for use in recovering channel assignment information.

2. A wireless mobile station for a wireless communication system, the mobile station comprising:

a transmitter configured, during an access state of the wireless communication system, to transmit a message representative of a call setup to at least one wireless base station of the wireless communication system; and

a receiver configured, during the access state, to (a) demodulate different received signals from a plurality of wireless base stations of the wireless communication system representing a first reply channel, associated with a first wireless base station, and a second reply channel, associated with a second wireless base station, to provide a respective first demodulated signal and a second demodulated signal, (b) decode the first demodulated signal to provide a first message, (c) decode the second demodulated signal to provide a second message, wherein the decoding of the first demodulated signal is independent of the decoding of the second demodulated signal, and (d) select one of the plurality of decoded messages for use in recovering channel assignment information during call setup.

3. The apparatus of claim 2 wherein the receiver comprises a RAKE receiver structure.

4. A method for use in a wireless mobile station of a wireless communication system during an access state of the wireless communication system, the method comprising the steps of:

transmitting a message to at least one wireless base station of the wireless communication system, the message representative of a call setup state of operation;

using message reception diversity to select one of a plurality of messages, each message independently decoded from one or more of a plurality of different demodulated received signals, the different received signals representing reply channels from a plurality of wireless base stations of the wireless communication system, the messages representing channel assignment information.

5. A wireless mobile station for a wireless communication system, the wireless mobile station comprising:

a transmitter configured, during an access state of the wireless communication system, to transmit a message to at least one wireless base station of the wireless communication system, the message representative of a call setup state of operation; and

a receiver configured, during the access state, to use message reception diversity by (a) demodulating different received signals, the different received signals representing reply channels from a plurality of wireless base stations of the wireless communication system, (b) decoding the different demodulated received signals to provide a plurality of messages, each message independently decoded from one or more of the plurality of wireless base stations and the messages representing channel assignment information, and (c) selecting one of the plurality of messages.