Apparatus for reducing a sampling frequency

Multiplex communications – Wide area network – Packet switching

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

370 84, H04J 105

Patent

active

042414431

ABSTRACT:
An apparatus for reducing a sampling frequency which derives information with the bandwidth f.sub.B /N (N is an integer) having a sampling frequency of 2f.sub.B /N from an input FDM signal with a bandwidth up to f.sub.B having the sampling frequency 2f.sub.B has been found. The present apparatus comprises a pair of partial frequency reduction systems and a switch for alternately selecting the outputs of said partial frequency reduction systems to provide the output signal. Each of said partial frequency reduction systems comprises a DFT means for performing the discrete Fourier transform for every G sampling points (G is the multiple of N) to said input signal, a multiplication means for multiplying the predetermined frequency characteristics with the output of said DFT means, linear conversion means for linear conversion of the output of said multiplication means and for providing G/N number of data, and means for performing the inverse discrete Fourier transform to the output of said linear conversion means. The present invention reduces sampling frequency by performing a smaller number of multiplications than a prior art, thus, the structure of an apparatus can be simple.

REFERENCES:
patent: 3605019 (1971-09-01), Cutter
patent: 3912870 (1975-10-01), Roy
patent: 4001510 (1977-01-01), Reed
patent: 4021616 (1977-05-01), Betts
patent: 4131766 (1978-12-01), Narasimha
IEEE Transactions on Communications; vol. Com-22, No. 9; Sep. 1974; "TDM-FDM Transmultiplexer . . . " by Bellanger.
IEEE Transactions on Communication Technology; vol. com-19; No. 1; Feb. 1971; "SSB/FDM Utilizing TDM Digital Filters" by Kurta.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Apparatus for reducing a sampling frequency does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for reducing a sampling frequency, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for reducing a sampling frequency will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2246557

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.