1
Philip F Kromer III, Rangarajan Srinivasagopalan, Raul F Fernandez: Carrier-phase adjustment using absolute phase detector. Racal Data Communications, William A Newton, July 15, 1986: US04601044 (61 worldwide citation)

Disclosed is a modulation-demodulation system and method for transmitting a plurality of sequentially received information bit sequences, the system including a transmitter having a state machine for expanding by a coding process each information bit sequence into an expanded bit sequence with a cod ...


2
Rangarajan Srinivasagopalan, James D Pruett, Vedavalli G Krishnan, Luis V Farias: Modem and method using multidimensional coded modulation. Racal Data Communications, William A Newton, August 2, 1988: US04761784 (27 worldwide citation)

Disclosed is a modem including a transmitter having a convolutional encoder for transforming each group interval digital data into an expanded bit sequence having symbol-selecting bits and a frame of subset-selecting bits forming a plurality of bit groups, with each bit group designating a 2-dimensi ...


3
Philip F Kromer, Rangarajan Srinivasagopalan, Raul F Fernandez: Modified absolute phase detector. Racal Data Communications, William A Newton, April 15, 1986: US04583236 (24 worldwide citation)

Disclosed is a modulation-demodulation system and method for transmitting a plurality of sequentially received information bit sequences, the system including a transmitter having a state machine for expanding by a coding process each information bit sequence into an expanded bit sequence with a cod ...


4
Rangarajan Srinivasagopalan, Louis V Farias: Method and apparatus for reduction of sinusoidal phase jitter in a high speed data modem. Racal Data Communications, Jerry A Miller, August 25, 1987: US04689804 (21 worldwide citation)

An apparatus for cancellation of sinusoidal varying phase jitter in a data modem is implemented in firmware using microprocessor technology. An estimate of the frequency and phase of the phase jitter is computed in a first stage. Substantially independently, an estimate of the amplitude of the phase ...


5
Rangarajan Srinivasagopalan, James D Pruett: Frame synchronization. Racal Data Communications, William A Newton, February 21, 1989: US04807230 (19 worldwide citation)

Disclosed is a modem including a transmitter having a convolutional encoder for transforming each group interval digital data into an expanded bit sequence having symbol-selecting bits and subset-selecting bits forming a plurality of bit groups, with each bit group designating a 2-dimensional subset ...


6
Henry H Parrish Jr, Rangarajan Srinivasagopalan: Digital transmitter with vector component addressing. Racal Data Communications, Jackson Jones & Price, April 10, 1984: US04442530 (11 worldwide citation)

A digital transmitter wherein a read only memory (ROM) is addressed by subaddresses representing vector components of signal point positions of a desired transmit spectrum. In this manner, greatly reduced ROM storage requirements are achieved.