39results about How to "Reduce demodulation complexity" patented technology

The embodiment of the invention provides a Bluetooth low-power-consumption multi-phase frequency shift keying modulation / demodulation method and device, and the method comprises the steps: grouping inputted binary data streams, each group comprising a plurality of bits; mapping the binary data stream into a phase sequence in which one binary data set is mapped into one phase of a predetermined phase set by Gray encoding; and modulating the phase sequence into a phase signal by using a phase waveform obtained by integrating a preset frequency waveform. When the baseband signal obtained based onthe phase signal is used for Bluetooth low-power-consumption signal transmission, high power amplification efficiency, low demodulation complexity and high anti-multipath interference performance canbe maintained while the BLE wireless transmission rate is improved.

The present invention provides a demodulation method, device, terminal, and system, wherein the demodulation method includes: acquiring communication information of a cell, performing blind solution to a synchronization signal in the communication information, and obtaining a blind solution result, The time range information carried in the communication information is determined according to the blind solution result, and the communication information is demodulated according to the time range information. The solution of the present invention can determine some conditions of the communication information of the cell by means of the obtained prior information, thereby reducing assumptions when demodulating the communication information, reducing demodulation complexity, and reducing power consumption.

The present application provides a signal transmission method, a base station, a terminal, and a communication system, wherein the signal transmission method includes: the base station determines the transmission period of the system signal transmitted by the base station, and the system signal is broadcast by the base station to multiple terminals signal; the base station sends the system signal according to the transmission cycle, and sends a deep coverage signal after sending the system signal every at least one transmission cycle, and the deep coverage signal carries the same signal as the system signal broadcast information. The application can improve the detection performance of the terminal to broadcast information, and increase the depth of signal coverage.

The invention is suitable for the field of the optical signal transmission, and provides a transmission system of a dual-polarization optical signal. The transmission system comprises a dual-polarization optical signal sending device, a transmission link and a dual-polarization optical signal receiving device connected in order; the dual-polarization optical signal sending device produces a multi-path optical signal with dual-polarization transmission information and sends the optical signal to the transmission link; the transmission link sends the optical signal to the dual-polarization optical signal receiving device through a multi-core optical fiber; the dual-polarization optical signal receiving device demodulates the optical signal to acquire the dual-polarization transmission information. Through the transmission system disclosed by the embodiment of the invention, the dual-polarization optical signal receiving device at a receiving end does not need a local laser and is unnecessary to integrate a coherent receiver, the receiving cost of the dual-polarization optical signal is greatly reduced, and the frequency offset compensation is inexistent since the local laser is not required, and the demodulation complexity of the system is reduced.

A time-domain OFDM synchronization symbol generation and demodulation method, data frame transmission method, wherein the generation method of the time-domain OFDM synchronization symbol includes generating a CAZAC sequence and its shift sequence; forming a frequency domain based on the CAZAC sequence and the shift sequence of the CAZAC sequence OFDM synchronization symbols; perform inverse Fourier transform on frequency domain OFDM synchronization symbols to form time domain OFDM synchronization training symbols; divide time domain OFDM synchronization training symbols into first part symbols and second part symbols, and divide these two parts symbols respectively Multiplied with a fixed frequency offset to form the prefix and suffix of the time-domain OFDM synchronization symbol; the time-domain OFDM synchronization symbol is formed based on the prefix of the time-domain OFDM synchronization symbol, the OFDM synchronization training symbol and the suffix of the time-domain OFDM synchronization symbol. The technical solution reduces the complexity of OFDM symbol generation, reduces the demodulation complexity and improves the demodulation parameter performance.

The invention belongs to the technical field of communication, and discloses a Chirp unequal error modulation method based on a plasma sheath channel, and an aircraft. At the signal transmitting end of the system, three different sequences m(t), n(t) and c are generated. (t), used to modulate the slope adjustment rate of the Chirp signal, carrier frequency and phase respectively; Chirp signal composite modulation; Chirp signal passes through the plasma sheath channel; After the signal passes through the plasma sheath channel, the signal received at the receiving end is respectively Do the fractional Fourier transform of the best order corresponding to the positive and negative slope adjustment, and sample the data at the best focus positions corresponding to different carrier frequencies; demodulate according to the sampled information to obtain the sent message sequence . The invention ensures that important information is sent out preferentially when the spaceship passes through the "black barrier" area. At the same time, compared with the existing FSK transmission scheme, the demodulation complexity is reduced, and the bit error rate is reduced at the same time.

The present invention provides a method, device, system, and storage medium for sending uplink information, wherein the method includes: determining an uplink antenna for sending first uplink information and second uplink information under the same subframe, wherein the The first uplink information includes at least one of the following: uplink sounding reference signal SRS, uplink detection signal, the second uplink information includes at least one of the following: uplink traffic channel signal, uplink control channel signal; use the determined above-mentioned uplink antenna to perform the first Sending processing of the first uplink information and the second uplink information. The present invention at least solves the problem in the related art that the antennas for sending uplink information in the same subframe are inconsistent.

The invention provides a non-uniform modulation and demodulation method and system in a wireless broadcast communication system, a medium and a terminal, and the method comprises the following steps:dividing a constellation point into four groups of different subsets, enabling the four groups of different subsets to respectively correspond to four different quadrants where a received signal falls, and calculating a search space corresponding to each subset; calculating the Euclidean distance between the constellation point of the search space corresponding to the quadrant and the received signal according to the quadrant to which the received signal belongs; and based on the calculated Euclidean distance, obtaining log likelihood ratio information through a Log _ Map or Max _ Log _ Map algorithm. According to the non-uniform modulation and demodulation method and system in the wireless broadcast communication system, the medium and the terminal, the complexity of non-uniform modulation and demodulation in the wireless broadcast communication system can be reduced, and no performance loss exists.