Digital tanlock loop for tracking π/4-DQPSK signals in digital cellular radio

Author

Wei, Che-Ho ; Chen, Wen-Jiang

Author_Institution

Inst. of Electron., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

43

Issue

3

fYear

1994

fDate

8/1/1994 12:00:00 AM

Firstpage

474

Lastpage

479

Abstract

A digital tanlock loop (DTL) is a nonuniform sampling digital phase-locked loop (DPLL) whose phase error detector, using the tan^-1[·] function with in-phase and quadrature samples of incoming signal, has a linear characteristic with a period of 2π. In this paper, we study the application of an N-phase DTL in digital cellular radio with π/4-DQPSK modulation. The performance degradation due to fading effect is investigated in terms of bit error rate and steady state phase error variance by computer simulation. It is shown that, in the digital cellular radio system, the performances on both bit error rate and phase error variance using DTL are far better than that using the traditional digital N-phase I-Q loop

Keywords

cellular radio; digital radio systems; phase shift keying; phase-locked loops; tracking; π/4-DQPSK signals tracking; DPLL; bit error rate; computer simulation; digital cellular radio; digital tanlock loop; fading effect; in-phase samples; linear characteristic; nonuniform sampling digital PLL; performance degradation; phase error detector; quadrature samples; steady state phase error variance; Application software; Bit error rate; Computer errors; Detectors; Digital modulation; Land mobile radio cellular systems; Nonuniform sampling; Phase detection; Phase locked loops; Tracking loops;

fLanguage

English

Journal_Title

Vehicular Technology, IEEE Transactions on

Publisher

ieee

ISSN

0018-9545

Type

jour

DOI

10.1109/25.312808

Filename

312808