Reliable conveyance of orthogonal space information

• US 7,158,556 B2
• Filed: 04/29/2002
• Issued: 01/02/2007
• Est. Priority Date: 04/29/2002
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Ho, Sai Yiu Duncan, Tiedemann, Edward G. Jr., Wei, Yongbin, Gaal, Peter
• Primary Examiner(s): TRAN, KHANH C
• Application Number:
  US10/135,551
• Publication Number:
  US 20030202561A1
• Time in Patent Office: 1,709 Days
• Field of Search: 375/141, 375/130, 375146-147, 370/209, 370/342, 370/345, 370/350, 370/322, 370/329, 370/335, 370/338
• US Class Current: 375/141
• CPC Class Codes: H04J 13/0048 Walsh
• CPC Class Codes: H04J 13/18 Allocation of orthogonal codes

Abstract

The contents of a counter at a remote station is used to select a Walsh cover, which is used to cover the acknowledgment or negative acknowledgment bits sent on a new reverse acknowledgment channel (R-ACKCH). In the new reverse acknowledgment channel, the value of the acknowledgment bits for the broadcast transmissions is used to select the Walsh code sequence that covers the acknowledgment bit for the dedicated transmissions. When a base station receives an acknowledgment message from the remote station, the base station checks the Walsh cover of the message and extracts the embedded counter content. If the embedded counter content of the received acknowledgment or negative acknowledgment differs from the local counter value, the base station determines that a synchronization problem occurred, such that the remote station is not operating with the current transmission format information. Hence, the counter values act as the sequence identifiers of the Walsh masks.

Claims

1. An apparatus in a base station for synchronizing Walsh space information between the base station and a remote station, comprising:

a local counter for tracking Walsh mask changes;

a memory element; and

a processing element communicatively coupled to the local counter and the memory element, wherein the processing element is configured to execute a set of instructions stored on the memory element, the set of instructions for;

receiving an acknowledgment message from the remote station, wherein the acknowledgment message has a Walsh cover that is selected by a counter value of a remote station counter,

determining the Walsh cover of the acknowledgment message;

extracting the counter content from the determined Walsh cover, and

resetting the local counter at the base station with the extracted counter content.

2. A method for synchronizing Walsh space information between a base station and a remote station, comprising:

receiving an acknowledgment message at the base station from the remote station, wherein the acknowledgment message has a Walsh cover that is selected by a counter value of a remote station counter,

determining the Walsh cover of the acknowledgment message;

extracting the counter content from the determined Walsh cover; and

resetting a local counter at the base station with the extracted counter content.

3. A method for maintaining synchronization between a local counter at a base station and a counter at a remote station, wherein the local counter and the counter are for counting the number of Walsh mask changes, comprising:

broadcasting the content of the local counter using a common medium access control identifier (MAC_ID);

receiving a MAC_ID) message by at least one remote station;

extracting the content of the local content from the MAC_ID; and

resetting the counters of the at least one remote station with the content of the local counter.

4. An apparatus in a remote station for resetting the contents of a counter at a base station, wherein the counter is for tracking the number of Walsh mask changes, comprising:

a memory element; and

a processing element configured to execute a set of instructions stored on the memory element, the set of instructions for;

generating a first acknowledgment message in response to a dedicated transmission from the base station;

selecting a Walsh code sequence in accordance to the contents of a local counter;

using the Walsh code sequence to cover the first acknowledgment message; and

transmitting the first covered acknowledgment message to the base station.

5. A method at a remote station for resetting the contents of a counter at a base station, wherein the counter is for tracking the number of Walsh mask changes, comprising:

generating a first acknowledgment message in response to a dedicated transmission from the base station;

selecting a Walsh code sequence in accordance to the contents of a local counter;

using the Walsh code sequence to cover the first acknowledgment message; and

transmitting the first covered acknowledgment message to the base station.

6. An apparatus far generating a combined acknowledgment message, wherein the combined acknowledgment message is for acknowledging a transmission and to reset a counter at a receiving party, comprising;

a repetition element for repeating an acknowledgment bit value to form a symbol;

a covering element for selecting a Walsh code symbol based on a local counter value; and

a multiplier for spreading the output of the repetition element with the output of the covering element.