Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
2006-04-04
2006-04-04
Chin, Stephen (Department: 2634)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
C375S222000, C375S296000, C375S298000, C375S350000, C370S210000
Reexamination Certificate
active
07023929
ABSTRACT:
A method of providing an improved transfer function for a Discrete Multitone (DMT) type modulation transmitter with digital filtering after modulation followed by digital to analog converter and analog filtering is provided by sending a test signal to said transmitter and measuring the results of the test signal to determine the transfer function. The inverse of the transfer function that needs to be compensated is determined and the inverse of transfer function to be compensated is truncated to the region of interest (H2). The desired band split component of pre-compensation filter is designed (H3). The desired target frequency response of the pre-compensation filter is determined by H4=H2*H3where H4is the multiplication of H2and H3Given the target frequency response in H4Hermetian symmetry is imposed on the frequency response. The inverse Fourier transform (IFFT) is taken to generate a time domain filter, h5. The characteristic of this filter is added at the digital filtering after modulation.
REFERENCES:
patent: 6097776 (2000-08-01), Mesiwala
patent: 6535552 (2003-03-01), Pessoa
patent: 6788725 (2004-09-01), Aoyagi et al.
patent: 6940807 (2005-09-01), Rezvani et al.
Dasgupta Udayan
Easwaran Prakash
Mujica Fernando A.
Oswal Sandeep
Sadafale Mangesh
Brady III W. James
Chin Stephen
Telecky , Jr. Frederick J.
Texas Instruments Incorporated
Wang Ted M.
LandOfFree
Digital pre-compensation filter for DMT type transmitter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Digital pre-compensation filter for DMT type transmitter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital pre-compensation filter for DMT type transmitter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3621792