Abstract:
A device for processing a radio frequency (RF) signal of an optical disk drive includes a high-pass (HP) filter, an RF variable gain amplifier (VGA), an RF analog-digital converter (ADC), and a digital module. The HP filter filters the RF signal and is capable of selectively utilizing one of a first cut-off frequency and a second cut-off frequency. The RF VGA amplifies the filtered RF signal. The RF ADC converts the amplified RF signal into a digital code. The digital module is capable of executing a first function and a second function with the digital code. The HP filter utilizes the first cut-off frequency when the digital module desires to execute the first function, and the HP filter utilizes the second cut-off frequency when the digital module desires to execute the second function.
Abstract:
A detector is scanned across an optical storage medium having groove tracks and land tracks, each track having a wobble structure, to detect light reflected from the optical storage medium. A wobble signal and a tracking error signal are generated based on an output of the detector, and the wobble signal is sampled according to the tracking error signal. A determination about whether the detector is at the groove track or the land track is made based on the tracking error signal and a comparison of sampled values of the wobble signal.
Abstract:
A signal processing apparatus includes sample and hold units for holding a plurality of analog photo diode signals. A signal holding controller generates control signals to the sample and hold units for holding the analog photo diode signals. Analog adjusting modules adjust the held analog photo diode signals. A multiplexer selectively couples one input end of the multiplexer to the output end of the multiplexer for outputting the adjusted analog photo diode signals. An analog to digital converter converts the adjusted analog photo diode signals into digital photo diode signals.
Abstract:
A device for detecting wobbles on an optical disc is provided, where the device is utilized for generating a wobble signal according to a plurality of detection signals. The device includes an analog signal processing circuit, a pair of analog-to-digital converters (ADCs), and a digital signal processing circuit. The analog signal processing circuit is arranged to perform analog signal processing on the detection signals to generate a plurality of output signals. In addition, the pair of ADCs are arranged to digitalize the output signals to generate a plurality of digital values. Additionally, the digital signal processing circuit is arranged to perform digital signal processing on the digital values and generate an arithmetic output, where the arithmetic output is utilized for generating the wobble signal or utilized as the wobble signal. An associated method for detecting wobbles on an optical disc is further provided.
Abstract:
An electrical device and a loop control method are provided. A data signal is obtained from a front end. A variable gain amplifier amplifies the data signal based on a gain value. An analog to digital converter samples the amplified data signal output therefrom to generate a digital data signal. A peak bottom detector detects a peak level and a bottom level of the digital data signal. A threshold controller compares the peak and bottom levels with a threshold value, and generates a first control signal accordingly. An auto gain controller updates the gain value based on the peak and bottom levels with a first step size. The first step size is determined by the first control signal.
Abstract:
An apparatus for detecting the wobble carrier frequency of an optical disk is disclosed. The apparatus comprises an offset canceller, a binary conversion module, an adjustable band pass filter, and a frequency detection module. The offset canceller cancels the direct current offset of a first wobble signal to obtain a second wobble signal. The binary conversion module converts the second wobble signal to a binary data stream. The adjustable band pass filter passes only an adjustable frequency range of the binary data stream to generate a filtered signal, wherein the center frequency of the adjustable frequency range is sequentially adjusted. The frequency detection module then determines maximum amplitude of the filtered signal, and determines the center frequency of the adjustable frequency range according to which the filtered signal with the maximum amplitude is generated, wherein the wobble carrier frequency is the center frequency corresponding to the maximum amplitude.
Abstract:
The invention provides an apparatus for controlling servo signal gains of an optical disc drive. The apparatus adjusts the gains of a plurality of servo signals controlling a servo system of the optical disc drive according to a closed-loop mode or a state-reloading mode whenever the optical disk drive encounters an operating state transition. In closed-loop mode, at least one AGC loop of the apparatus compensates the gains of the servo signals with a selectable bandwidth during a specific period after the operating state transition to accelerate the convergence of the servo signals. In state-reloading mode, at least one AGC loop of the apparatus reloads the previously saved convergence values or pre-determined values as the initial values according to the current operating state immediately after the operating state transition to accelerate the convergence of the servo signals.
Abstract:
A method for deriving a tracking error signal based on a first analog detection signal and a second analog detection signal. The method includes summing the first analog detection signal and the second analog detection signal to generate an analog sum signal. An analog delay device is utilized to delay the analog sum signal to be a delay signal. The delay signal is digitalized into a digital delay signal. The first analog detection signal and the second analog detection signal are respectively transformed into a first digital detection signal and a second digital detect signal. The tracking error signal is then generated utilizing a comparing operation among the digital delay signal, the first digital detect signal, and the first digital detect signal.
Abstract:
A system, for tuning a plurality of write strategy parameters of an optical storage device, includes: a run-length limited (RLL) meter for detecting a plurality of lengths, each length corresponding to a pit or a land on an optical storage medium accessed by the optical storage device; and a calculation module coupled to the RLL meter for performing calculations according to the lengths to generate a plurality of calculation results; wherein the write strategy parameters are tuned according to the calculation results.
Abstract:
A device for detecting wobbles on an optical disc is provided, where the device is utilized for generating a wobble signal according to a plurality of detection signals. The device includes an analog signal processing circuit, a pair of analog-to-digital converters (ADCs), and a digital signal processing circuit. The analog signal processing circuit is arranged to perform analog signal processing on the detection signals to generate a plurality of output signals. In addition, the pair of ADCs are arranged to digitalize the output signals to generate a plurality of digital values. Additionally, the digital signal processing circuit is arranged to perform digital signal processing on the digital values and generate an arithmetic output, where the arithmetic output is utilized for generating the wobble signal or utilized as the wobble signal. An associated method for detecting wobbles on an optical disc is further provided.