摘要:
A system and a method for deriving transmitted signals from multiple users for an OFDM-CDMA communication system are described herein. An optimum synchronizer for use in an OFDM-CDMA system is also provided. In one aspect, the system and method incorporate a programmable structure for different OFDM-CDMA systems (e.g., MC-CDMA, MC-DS-CDMA, and MT-CDMA) that can be efficiently implemented. The programmable structure is based on the linear minimum mean square error (LMMSE) or best linear unbiased estimator (BLUE) techniques. In addition, an efficient algorithm for reducing computations of fast Fourier transform (FFT) is presented.
摘要:
A broadcast receiver includes a tuner circuit and a demodulator circuit. The tuner circuit tunes a radio frequency (RF) signal to output an intermediate frequency (IF) signal. The demodulator circuit demodulates the IF signal from the tuner circuit and outputs a command signal based on the quality of the IF signal, for changing a take over point (TOP) value, preset in the tuner circuit, at which one amplitude gain control (AGC) stopping and another taking over. A method for regulating a broadcast receiver is also disclosed herein.
摘要:
Disclosed is an automatic video gain control circuit, which includes an analog to digital converter, an envelope detector and an extreme value detector. The analog to digital converter converts an analog video signal to a digital video signal. The envelope detector detects a baseband amplitude signal according to the digital video signal. The extreme value detector generates an extreme value to control RF signal gain.
摘要:
A broadcast receiver includes a tuner circuit and a demodulator circuit. The tuner circuit tunes a radio frequency (RF) signal to output an intermediate frequency (IF) signal. The demodulator circuit demodulates the IF signal from the tuner circuit and outputs a command signal based on the quality of the IF signal, for changing a take over point (TOP) value, preset in the tuner circuit, at which one amplitude gain control (AGC) stopping and another taking over. A method for regulating a broadcast receiver is also disclosed herein.
摘要:
A smart channel scan method and associated apparatus, for searching center frequencies and symbol rates of the video signal channels. The smart channel scan method performs spectrum analysis for the video signal to generate a power spectrum density signal and obtain a plurality of center frequencies and coarse bandwidth. Symbol rates are determined according to the power spectrum density signal and the coarse bandwidth.
摘要:
Disclosed is an automatic video gain control circuit, which includes an analog to digital converter, an envelope detector and an extreme value detector. The analog to digital converter converts an analog video signal to a digital video signal. The envelope detector detects a baseband amplitude signal according to the digital video signal. The extreme value detector generates an extreme value to control RF signal gain.