Title :
AFC circuit with fast acquisition for a TDMA cellular mobile communication system
Author :
Ohishi, Y. ; Fukuda, E. ; Kubo, T. ; Takano, T. ; Daido, Y.
Author_Institution :
Fujitsu Lab. Ltd., Kawasaki, Japan
Abstract :
A novel AFC (automatic frequency control) circuit for a TDMA (time-division multiple-access) digital cellular mobile communication system with π/4-shifted QPSK (quadrature phase-shift keying) modulation is described. The AFC circuit satisfies the two contradictory requirements of fast acquisition and stable operation even under low CNR (carrier-to-noise ratio) channel conditions, simultaneously. The performance of a 40-kb/s TDMA transmission system was measured to confirm the availability of the AFC circuit. An Eb/ N0 penalty of the differential demodulator is compressed to less than 0.1 dB by the AFC circuit when carrier frequency deviation is within ±1 kHz. The results obtained show that the differential detection can be applied to a receiver of the TDMA digital cellular mobile communication system when the proposed AFC circuit is implemented
Keywords :
automatic frequency control; cellular radio; digital radio systems; phase shift keying; time division multiple access; π/4-shifted QPSK; 40 kbit/s; AFC circuit; TDMA; automatic frequency control; carrier-to-noise ratio; differential detection; digital cellular mobile communication system; fast acquisition; quadrature phase-shift keying; Automatic frequency control; Circuits; Communication system control; Control systems; Digital modulation; Mobile communication; Phase modulation; Phase shift keying; Quadrature phase shift keying; Time division multiple access;
Conference_Titel :
Vehicular Technology Conference, 1991. Gateway to the Future Technology in Motion., 41st IEEE
Conference_Location :
St. Louis, MO
Print_ISBN :
0-87942-582-2
DOI :
10.1109/VETEC.1991.140473
