Pulse or digital communications – Receivers – Automatic frequency control
Patent
1997-02-06
2000-02-01
Pham, Chi H.
Pulse or digital communications
Receivers
Automatic frequency control
375329, 348731, H04L 2706
Patent
active
060211652
ABSTRACT:
To control the oscillation frequency of a local oscillator, a digital broadcast receiver demodulates a phase-reference symbol contained in an orthogonal frequency-division multiplexed broadcast signal. The resulting frequency-domain data are modified by multiplication with complex conjugates of the known data encoded in the phase-reference signal, under different assumed frequency offsets between the frequency-domain data and known data. The results are converted to time-domain data, yielding one time series for each assumed frequency offset. One value is taken from each time series, these values are compared, and the oscillation frequency is adjusted according to the comparison results.
A digital broadcast receiver for receiving a PSK-OFDM signal, having a local oscillator with a controllable oscillation frequency, a mixer for down-converting said PSK-OFDM signal to an intermediate-frequency signal by mixing said PSK-OFDM signal with a signal generated by said local oscillator, and demodulating circuits for obtaining an array of frequency-domain data from said intermediate-frequency signal, said array of frequency-domain data representing subcarrier phase information of said PSK-OFDM signal. The digital broadcast receiver further including a phase modifying means, an inverse-fast-Fourier-transform means, a peak detecting means, and a frequency-deviation detector. The digital broadcast receiver can also include a data selecting means in addition to the elements previously described.
REFERENCES:
patent: 4887050 (1989-12-01), Borth et al.
patent: 5239400 (1993-08-01), Liu
patent: 5444697 (1995-08-01), Leung et al.
patent: 5450456 (1995-09-01), Mueller
patent: 5471464 (1995-11-01), Ikeda
patent: 5790784 (1998-08-01), Beale et al.
Schulze, H., "Digital Audio Broadcasting (DAB) --Stand der Entwidklung", IN : Bosch Technische Berichte, 1991, Issue 54, pp. 17-25.
Ohkubo Tadatoshi
Ohsuga Yoshiharu
Taura Ken-ichi
Tsujishita Masahiro
Mitsubishi Denki & Kabushiki Kaisha
Pham Chi H.
Webster Bryan
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