Abstract: At a base station 2, a CDMA received signal coming in through an antenna 4 is fed to a radio frequency unit (RFU) or high frequency unit 6. The RFU 6 demodulates a baseband signal BB from a signal RF and delivers the signal BB to an analog-to-digital converter (A/D) 8. The resulting digital signal output from the A/D 8 is input to a hybrid interference canceller (HIC) 12 as a received signal Rx Data 10. The HIC 12 divides users into two groups and assigns one combination of a parallel interference canceller and a serial interference canceller to each group. The HIC 12 cancels interference contained in the received signal Rx Data 10 for thereby estimating symbols particular to a plurality of users.
August 30, 1999
Date of Patent:
December 9, 2003
Oki Techno Centre Pte. Ltd., National University of Singapore
Hiroki Sugimoto, Teng Joon Lim, Lars Rasmussen, Kok Leong Cheah, Sumei Sun, Yoshihiro Matsumoto, Takashi Oyama
Abstract: A pulse density modulator unit transforms an N-bit input signal representing an input value, into an output digital signal having a digital pulse density which is a linear function of the input value. The pulse density modulator unit includes a first pulse density modulator which produces a binary signal representing a multiplication factor as a pulse density. It further includes a combination module which receives the input signal, the binary signal from the first pulse density modulator and an offset control signal. The combination module produces a combined signal which, on average, represents the product of the input signal and the amplification control signal, offset by an amount dependent upon the offset control signal. A second pulse generator uses the combined signal to generate the output digital signal. The combination module may be a selector.
September 24, 2001
April 25, 2002
Oki Techno Centre Pte Ltd
Tao Zhang, Hiroshi Katsuragawa, Noriyoshi Ito
Abstract: A single frequency relay station receives a signal from a master station, and retransmits it. Before retransmitting the signal, the relay station uses a digital filter to subtract from the signal components which arise from multipath interference and coupling interference. The coefficients used by the digital filter are derived from characteristics of the multipath interference and the overall transfer function of the relay station. These are derived by turning off the retransmission, so that the multipath interference can be estimated from the received signal, and commencing the retransmission again, to determine the transfer function. A simplified inverse fast Fourier transform is used to simplify the calculations.
Abstract: Methods and structures are disclosed which realize high Q inductors to provide on-chip noise matching of microwave monolithic integrated circuits, such as low noise amplifiers and output matching networks for power amplifiers. High Q inductors, of typically 6nH, are devised by using the inductance of package leads, bondwires, electronic board trace wires and transmission lines and other components in various configurations. These and other components are serially connected starting from a chip pad, representing a circuit node, to a circuit input on a that electronic board.
October 13, 1998
Date of Patent:
December 19, 2000
Institute of Microelectronics, Oki Techno Centre Pte Ltd.
Rajinder Singh, Kai Tuan (Kelvin) Yan, Junichi Shibata