Pulse or digital communications – Receivers – Angle modulation
Patent
1995-10-11
1996-12-31
Tse, Young T.
Pulse or digital communications
Receivers
Angle modulation
375332, 375344, 329304, H03D 322, H04L 2722
Patent
active
055901581
ABSTRACT:
An in-phase component and a quadrature component of a digitized input DQPSK modulated signal are provided from interpolation filters, respectively. An instantaneous amplitude and an instantaneous phase of the input signal for each symbol clock are detected from the in-phase and quadrature components and are fed to adders. At the same time, that one of symbols "0, 0," "0, 1," "1, 0" and "1, 1" which corresponds to the instantaneous phase is detected by a symbol detector. An ideal reference signal generating part generates an ideal amplitude component and an ideal phase component corresponding to the detected symbol and provides them to a parameter calculating part. In an I-Q origin offset detecting part, an I-Q origin offset is calculated on the basis of the relationship between a triangle formed by the current detected vector corresponding to an ideal symbol and a vector detected one symbol clock before and a triangle formed by the said two vectors. An amplitude and a phase corresponding to the calculated I-Q origin offset are provided to the adders, respectively, and are corrected with respect to the detected instantaneous amplitude and phase, thereafter being fed to the parameter calculating part 22. In the parameter calculating part, a transmitter gain, and an amplitude variation, offset frequency and phase error per symbol clock are calculated.
REFERENCES:
patent: 5079512 (1992-01-01), Muto
patent: 5187719 (1993-02-01), Birgenheier et al.
patent: 5440587 (1995-08-01), Ishikawa et al.
Nakada Juichi
Tajiri Shinsuke
Yamaguchi Takahioro
Advantest Corporation
Tse Young T.
LandOfFree
Method and apparatus for estimating PSK modulated signals does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for estimating PSK modulated signals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for estimating PSK modulated signals will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1147641