Wireless telephone with excitation reconstruction of lost packet

• US 6,678,267 B1
• Filed: 12/14/1999
• Issued: 01/13/2004
• Est. Priority Date: 08/10/1999
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Viswanathan, Vishu R., McCree, Alan V., Anandakumar, Krishnasamy
• Primary Examiner(s): HO, DUC CHI
• Application Number:
  US09/461,677
• Time in Patent Office: 1,491 Days
• Field of Search: 370/235, 370/252, 370/253, 370/286, 370/310, 370/352, 370/356, 370/389, 370/392, 370/394, 370/436, 370/437, 370/465, 370/468, 370/474, 370/516, 370/330, 704/500, 704/264, 704/219, 704/223, 709/231-234, 709/247, 714/750, 714/760, 375/225, 375/287, 375/299, 375/371, 375/222, 375/347, 375/141-143
• US Class Current: 370/356
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/6418 Hybrid transport

Abstract

A process (111,101) of sending packets of real-time information at a sender (311) includes steps of initially generating at the sender the packets of real-time information with a source rate (s11) greater than zero kilobits per second, and a time or path or combined time/path diversity rate (d11), the amount of diversity (d11) initially being at least zero kilobits per second. The process sends the packets, thereby resulting in a quality of service QoS, and optionally obtains at the sender (311) a measure of the QoS. Rate/diversity adaptation decision may be performed at receiver (361′) instead. Another step compares the QoS with a threshold of acceptability (Th1), and when the QoS is on an unacceptable side of said threshold (Th1) increases the diversity rate (d11 to d22) and sends not only additional ones of the packets of real-time information but also sends diversity packets at the diversity rate as increased (d22).

Claims

1. A wireless telephone comprising:

an antenna,

a voice transducer, and

at least one integrated circuit assembly coupling the voice transducer to the antenna, said at least one integrated circuit assembly providing voice over packet transmission and reception and including processor instruction bits defining reconstruction of a packet stream with each packet having a primary stage and a secondary stage, the secondary stage having Linear Predictive Codind (LPC) parameters, and at least one of Longterm Prediction (LTP) lags, parity check, and adaptive and fixed codebook gains, the received packet stream having an instance of single packet loss, and the reconstruction comprising;

i. receiving a packet sequence represented by P(n)P(n−

1)′

, P(n+2)P(n+1)′

, and P(n+3)P(n+2)′

;

ii. obtaining as information from the secondary stage the LPC parameters, and the at least one of LTP lags, parity check, and adaptive and fixed codebook gains; and

iii. performing an excitation reconstruction of the lost packet utilizing the received information.

2. The wireless telephone of claim 1 in which the processor instruction bits define the performing an excitation to produce the following reconstructed packet sequence:

3. The wireless telephone of claim 1 in which the secondary stage includes no fixed codebook pulses, and the processor instruction bits further define performing an excitation with an adaptive codebook contribution reconstructed from the adaptive codebook gain and LTP lag.

4. The wireless telephone of claim 1 in which the secondary stage includes no fixed codebook pulses, and the processor instruction bits further define performing an excitation with an adaptive codebook contribution set to zero if the absolute value of the adaptive codebook gain is less than 0.4.

5. The wireless telephone of claim 1 in which the secondary stage includes fixed codebook pulses, and the processor instruction bits further define performing an excitation with the fixed codebook pulses.

6. The wireless telephone of claim 1 in which the secondary stage includes some of all the possible fixed codebook pulses, and the processor instruction bits further define performing the excitation with the some of all the possible fixed codebook pulses.

7. The wireless telephone of claim 1 in which the processor instruction bits further define performing an excitation with the fixed codebook pulses, other than the some of all the possible fixed codebook pulses, set to zero.