Fractional Speech Loss and Talker Activity Model for TASI and for Packet-Switched Speech

Author

Weinstein, Clifford J.

Author_Institution

M.I.T. Lincoln Lab., Lexington, MA

Volume

26

Issue

8

fYear

1978

fDate

8/1/1978 12:00:00 AM

Firstpage

1253

Lastpage

1257

Abstract

The cutout fraction in a TASI system is shown to be $\\phi=frac{1}{np}\\sum _{k=c+1}^n (k-c) n\\choose k p^{k}(1-p)^{n-k}$ where $n$ is the number of sources, $c$ is the number of channels, and $p$ is the probability that a source is issuing a talkspurt at a random time. This result is shown to hold independently of the probability density function of talkspurt duration. The same formula is shown to apply to the fraction of packets lost in a packet-switched link with a transmission capacity of $c$ packets every Tpseconds, where Tpis the interval between packet generations for an individual source during talkspurt, and where no packet is queued for a time longer than Tp. In addition, a simple Markov birth-death model is presented for the random process $a(t)$ representing the number of talkers issuing talkspurts at a given time.

Keywords

Packet switching; Queued communications; Speech transmission; Bit rate; Computer simulation; Equations; Error probability; Gaussian noise; Noise measurement; Quadrature phase shift keying; Speech; Statistics; White noise;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/TCOM.1978.1094198

Filename

1094198