Synchronization of timing advance and deviation

• US 7,573,913 B2
• Filed: 02/25/2002
• Issued: 08/11/2009
• Est. Priority Date: 04/06/2000
• Status: Expired due to Fees

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Terry, Stephen E.
• Primary Examiner(s): Ngo; Ricky
• Assistant Examiner(s): NG, CHRISTINE Y
• Application Number:
  US10/082,844
• Publication Number:
  US 20020080749A1
• Time in Patent Office: 2,724 Days
• Field of Search: 370/310, 370/312, 370/321, 370/324, 370/336, 370/337, 370/442, 370/468, 370/471, 370503-517, 370/328, 370/347, 370/349, 370/350, 375354-357, 455/13.2, 455/132
• US Class Current: 370/509
• CPC Class Codes: H04B 7/2681 Synchronisation of a mobile station with one base station
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 92/10 between terminal device and access point, i.e. wireless air interface

Abstract

A system and method for reducing the latency from timing deviation (TD) measurement to time advance (TA) adjustment. The invention uses a deterministic procedure to coordinate time advance (TA) commands and timing deviation (TD) measurements so that failed transmissions or mobile terminals signal propagation changes can be recognized and corrected much more rapidly. Radio resource efficiency is maximized by minimizing signaling overhead through effectively reducing the frequency of time advance commands. This is accomplished by using TA command signals which include a Connect Frame Number (CFN) to specify particular radio frames for time advance (TA) adjustment. The potential for timing deviation (TD) measurements to be incorrectly processed in conjunction with adjusting a physical reception window and calculating mobile termination location is minimized, without excessive command signaling requirements.

Claims

1. A method of using a mobile terminal for synchronizing uplink signals in wireless communications that use a time frame format having sequentially identified system time frames, the method comprising:

receiving communication data within system time frames including a timing advance signal which include timing advance data and a Connect Frame Number specifying a specific frame for effectuating a timing adjustment; and

adjusting uplink transmission timing of the mobile terminal in response to timing advance data in the received timing advance signal commencing in the time frame specified in the Connect Frame Number of the received timing advance signal.

2. A mobile terminal which supports wireless bi-directional communications via the utilization of a time frame format having sequentially identified system time frames, the mobile terminal comprising:

a receiver, a transmitter and an associated processor;

said receiver configured to receive communication data within system time frames including timing advance signals which include data and a Connect Frame Number specifying a specific frame for effectuating a timing adjustment;

said transmitter configured to transmit selectively formatted communication data within system time frames synchronized by said processor; and

said mobile terminal processor configured to adjust transmission timing of said transmitter in response to timing advance data in a received timing advance signal commencing in the time frame specified in the Connect Frame Number of the received timing advance signal.

3. A mobile terminal comprising:

a receiver, a transmitter and an associated processor;

said receiver configured to receive wireless communication signals within sequentially identified time frames including timing advance signals which include timing advance data and a Connect Frame Number specifying a specific frame for effectuating a timing adjustment;

said transmitter configured to transmit selectively formatted wireless communication signals within sequentially identified time frames synchronized by said processor; and

said processor configured to adjust transmission timing of said transmitter in response to timing advance data in a received timing advance signal commencing in the time frame specified in the Connect Frame Number of the received timing advance signal.

4. A method for synchronizing wireless communication signals by a mobile terminal comprising:

receiving wireless communication signals within sequentially identified time frames including timing advance signals which include timing advance data and a Connect Frame Number specifying a specific frame for effectuating a timing adjustment; and

adjusting the timing of wireless communication signal transmissions of the mobile terminal in response to timing advance data in a received timing advance signal commencing in the time frame specified in the Connect Frame Number of the received timing advance signal.