Patent ID: 6744757
Filing Date: 2004-06-01
Classification: H04L

Abstract:
A private branch exchange comprising:A. telephone interface circuitry having plural connectors ready for connection to plural telephone units; B. a digital network interface ready for connection to a public switched telephone network; and C. at least one integrated circuit assembly coupling the telephone interface circuitry to the digital network interface, said at least one integrated circuit assembly providing voice over packet transmission and reception and holding processor instruction bits defining reconstruction of a packet stream with each packet having a primary stage and a secondary stage, the secondary stage having LPC parameters, and at least one of 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(nâˆ’1)â€², [Lost Packet], P(n+2)P(n+1)â€², and P(n+3)P(n+2)â€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.