摘要:
A MIMO detection method for a receiver in a MIMO system using N-QAM for modulation, the MIMO detection method including generating a plurality of symbol vector sets and a plurality of search radiuses, selecting a candidate symbol vector set corresponding to a highest level of a multilevel structure of N-QAM constellation, generating a search space corresponding to a lower level of the multilevel structure of N-QAM constellation according to the selected candidate symbol vector set, confirming which level the search space corresponds to, and generating a detection signal according to the search space when the level of the search space is the lowest level of the multilevel structure of the N-QAM constellation.
摘要:
A MIMO detection method for a receiver in a MIMO system using N-QAM for modulation, the MIMO detection method including generating a plurality of symbol vector sets and a plurality of search radiuses, selecting a candidate symbol vector set corresponding to a highest level of a multilevel structure of N-QAM constellation, generating a search space corresponding to a lower level of the multilevel structure of N-QAM constellation according to the selected candidate symbol vector set, confirming which level the search space corresponds to, and generating a detection signal according to the search space when the level of the search space is the lowest level of the multilevel structure of the N-QAM constellation.
摘要:
A receiver having Inphase-Quadrature (I-Q) imbalance compensation and an I-Q imbalance compensation method are provided. The receiver calculates a cross-ratio parameter according to a first ideal receiving value and a first ideal conjugate receiving mirror of a first receiving signal and a second ideal receiving value and a second ideal conjugate receiving mirror of a second receiving signal. The receiver calculates an I-Q imbalance compensation parameter according to the cross-ratio parameter, the first ideal receiving value, the first ideal conjugate receiving mirror, the second ideal receiving value, the second ideal conjugate receiving mirror, the first receiving signal and the second receiving signal. The receiver compensates a third receiving signal according to the I-Q imbalance compensation parameter.
摘要:
A receiver having Inphase-Quadrature (I-Q) imbalance compensation and an I-Q imbalance compensation method thereof are provided. The receiver calculates a cross-ratio parameter according to a first ideal receiving value and a first ideal conjugate receiving mirror of a first receiving signal and a second ideal receiving value and a second ideal conjugate receiving mirror of a second receiving signal. The receiver calculates an I-Q imbalance compensation parameter according to the cross-ratio parameter, the first ideal receiving value, the first ideal conjugate receiving mirror, the second ideal receiving value, the second ideal conjugate receiving mirror, the first receiving signal and the second receiving signal. The receiver compensates a third receiving signal according to the I-Q imbalance compensation parameter.
摘要:
A method and apparatus for measuring an elapsed time from a starting signal to an ending signal in a time-to-digital converter. Primarily, the invention calculates an amount of complete cycles from the starting signal to a starting edge of a next clock cycle or the next Nth clock cycle (N is a natural number great than one) after the clock cycle corresponding to the ending signal. The amount is multiplied by a cycle time of the coarse clock to obtain a coarse time value. A time residue is calculated from the ending signal to the starting edge. Finally, the time residue is subtracted from the coarse time value to obtain a required time.
摘要:
An all-digital clock generator includes a digitally-controlled clock generator and a processing unit. The digitally-controlled clock generator generates a clock signal in response to an enable signal and a digital signal. The processing unit has a frequency multiplier and a reference signal having a period, digitizes the period to generate a quantized signal, generates the digital signal according to the quantized signal and the frequency multiplier, and generates the enable signal according to the reference signal, the clock signal and the frequency multiplier.
摘要:
A tangent angle computation device and associated DQPSK decoder. The computation device uses an eight-bit divider and a four-quadrant technique for finding a quantized angular value from an incoming signal. The quantized angular value is subsequently used to decode the incoming signal.
摘要:
An all-digital clock generator includes a digitally-controlled clock generator and a processing unit. The digitally-controlled clock generator generates a clock signal in response to an enable signal and a digital signal. The processing unit has a frequency multiplier and a reference signal having a period, digitizes the period to generate a quantized signal, generates the digital signal according to the quantized signal and the frequency multiplier, and generates the enable signal according to the reference signal, the clock signal and the frequency multiplier.
摘要:
A method and device for frequency synthesizing, in which the digital frequency synthesizer includes a clock pair having two similar ring-oscillators to separately generate a search frequency and an output frequency, a frequency tracking unit, and a clock controlling unit. The frequency-search method includes two stages: one stage is the coarse search stage based on the "Prune-and-Search", and other stage is the fine search stage based on the "fixed-step" algorithm. In order to determine which search scheme is used to search the target frequency and to determine the lock status, two cost functions for search and lock-in are derived. These two cost functions define the search threshold and the lock threshold, and these thresholds define the cost window and the lock window. If the frequency error is higher than both the search and lock thresholds, a coarse search is activated to estimate the correct frequency. And only when the frequency error falls between the search and the lock thresholds, should the fine search be activated. By properly assigning these two thresholds, the search performance, such as tinting and frequency error, and the output resolution can be improved. The digital frequency synthesizer which can be designed at HDL level and synthesized as part of a target cell library.