摘要:
In case microcontroller and digital signal processing blocks are used together in one chip, there has been a problem in which the synchronization of the clocks are not consistent with each other when sending a signal from one block to another. In addition, when a reference clock is activated during a change of input signal, an incomplete interval has occurred. Accordingly, in order to solve the above mentioned problem, the present invention discloses a synchronizing circuit which uses a latch circuit("RS") consisted of NAND gates to synchronize an asynchronous input data and a reference clock, thereby solving the problem in which an incomplete interval occurs.
摘要:
A hadamard code generation circuit is disclosed. The circuit includes a start reset signal generator for generating a start reset signal START.sub.-- RESET when a 6-bit output signal REF.sub.-- C from the 6-bit reference counter, a higher 4-bit index output signal H(5:2) of the 6-bit register and a 2-bit value from a ground circuit are identical; a "0" value force allocation unit for outputting a FORCE.sub.-- 0.sub.-- DEL signal for forcibly allocating all values of the 0th column to "0" when a 4-bit output signal REF.sub.-- C (5:2) from the 6-bit reference counter and a 4-bit value from the ground circuit are identical; a 2-bit counter for receiving the start reset signal and an external clock signal, outputting lowest bit signals C1 and C0 and outputting a carry-out signal; a 4-bit counter operated in accordance with a result that an inverted FORCE.sub.-- 0 signal and a carry-out signal are ANDed and outputting higher bit signals C4, C3 and C2; a 4th hadamard code generator for logically processing a lower 2-bit output signal from the 2-bit counter and a lower 2-bit index value from the 6-bit register and generating a 4-th hadamard code; a 12th paley code generator for generating a 12th paley code using an output signal from the counter and the FORCE.sub.-- 0.sub.-- DEL signal and the ALL.sub.-- ZERO signal; and a 48th hadamard code generator for logically processing a 4th hadamard code and a 12th paley code and generating a 48th hadamard code.
摘要:
A wireless modem is mounted to a terminal for wireless communication, and specifically controls an internal drive clock to reduce power consumption in an active mode. The wireless modem includes: a wireless core module for transmitting and receiving a radio signal; a modulator for converting data to be transmitted into a wireless transmission signal and transmitting the converted signal to the wireless core module; a demodulator for converting the signal received from the wireless core module into reception data; a synchronizer for synchronizing the signal received from the wireless core module; and a clock controller for generating a drive clock of each of the modulator, the demodulator, and the synchronizer. A low power clock controller is divided into six main functional blocks of a synchronizer, an analog controller, a modulator, a channel decoder, a demodulator, and a channel encoder, and has a feature that a clock is input only when a main functional block operates. As a result, it is possible to minimize power consumption caused by clock switching when an Orthogonal Frequency Division Multiplexing Access (OFDMA) mobile station modem operates in an active mode through the clock controller.
摘要:
A method for stable channel estimation to increase frequency band efficiency that is lost by using a pilot, and to reduce the complexity and the sensitivity to channel zero. The method includes generating an i-th symbol block Si including N carriers, performing an inverse fast Fourier transform (IFFT) operation on the i-th symbol block, and forming an orthogonal frequency division multiplexing (OFDM) symbol block. The method also includes attaching a guard interval sample in front of the i-th OFDM symbol block Ui and forming at least one OFDM symbol block Ui,cp. The method further includes modeling the formed OFDM symbol block Ui,cp with a channel finite impulse response (FIR) filter and estimating channel impulse response using signals yi received through a channel.
摘要:
Provided is a receiver of a multi-input multi-output system using multiple antennas, the receiver including: a first multiplying unit for multiplying a vector r received via the antenna by a Hermitian matrix Q; a candidate transmitting vector generating unit for detecting a signal on a lowest modulation order transmitting antenna from the received vector y output from the first multiplying unit, creating as many symbol candidates as the modulation order of the detected signal, and generating a candidate transmitting vector using each symbol candidate; a transmitting vector determining unit for obtaining a distance between each candidate transmitting vector generated by the candidate transmitting vector generating unit and the received vector y to determine a final transmitting vector; and a demodulating unit for demodulating the final transmitting vector determined by the transmitting vector determining unit. Since the receiver detects a transmitting vector with reference to a signal on a lowest modulation order transmitting antenna, the receiver can have a simpler structure.
摘要:
Disclosed is a method for receiving an analog signal from a receiver supporting at least a first channel band and a second channel band. The method for receiving an analog signal includes sampling the analog signal received through an antenna, generating a decimated signal by passing the sampled signal to a CIC decimation filter; and inputting the decimated signal to a channel selection filter.
摘要:
The present invention relates to a digital front end receiver using a DC offset compensation scheme. The digital front end receiver includes a DC offset compensation filter configured to remove DC offset components from signals received from a digital mixer and a Cascaded Integrator-Comb (CIC) decimation filter configured to reduce a sampling rate of the signals received from the DC offset compensation block.
摘要:
This invention is regarding mobile communication digital receiver and operating methods of a digital front end, which uses a digital mixer to change the center frequency to DC; a digital mixer allows the user to evade I/Q mismatch challenges; an Analog-to-Digital Converter (ADC) converts a Radio Frequency analog signal to a digital signal; a digital mixer converts the ADC's output signal's center frequency to DC; a digital front end has an automatic gain control over multiple frequency bands and contains a noise filter; a modem receives the digital front end's output and demodulates the signal.
摘要:
A region searcher, a method of driving the same, and a code searcher using the same are disclosed. When a predetermined region is iteratively searched, the energy value corresponding to the same hypothesis location value is stored by using a searcher having divided two buffers, thereby the implementation complexity thereof can be remarkably reduced, without using a simple memory.In addition, in case where the region is iteratively searched in the state of the deteriorated signal-to-noise ratio to find the energy value at one hypothesis location and in case where the region must be iteratively searched because of the restriction which the size of the matched filter can be not increased, the implementation complexity thereof can be remarkably reduced.
摘要:
A digital RF receiver does not use a separate receiver according to a mode and a band for multi-mode reception, MIMO reception, and bandwidth extension reception, and changes only setting variables in a single receiver structure so as to implement multi-mode reception, MIMO reception, bandwidth extension reception, and/or simultaneous multi-mode operation, such that complexity of the receiver, development cost, and power consumption can be reduced.