16 results about "Time diversity" patented technology

This invention discloses a multi-domain joint error correction system for a dual-frequency swarm array, belonging to the field of radar signal processing technology. It obtains correction signals from multiple correction sources through time diversity, with each source transmitting correction signals to the swarm array with a position error exceeding half a wavelength via two carrier frequencies. A simplified SMSSWF method is used to estimate the actual steering vectors of the two carrier frequencies. Based on these steering vectors, the equivalent frequency method is used to calculate the position error, obtaining estimated values ​​for the array element position error parameters. After updating the array element position information using these estimated values, the received signals from the two carrier frequencies are used to estimate the position error, phase error, and communication delay error, respectively, completing the joint error correction for the swarm array with a position error exceeding half a wavelength. The dual-frequency position error estimation based on the equivalent frequency method fully utilizes the large error estimation range of the dual-frequency method while retaining the high accuracy of traditional methods, successfully correcting errors even when the position error exceeds half a wavelength.

The application provides a satellite joint channel estimation method, system, device and medium based on CRDSA, and belongs to the technical field of space-air communication. The method comprises the following steps: acquiring an access waveform corresponding to a current time frame; using at least two time slots in the current time frame to send the same service copy package by an access node; performing time-slot-by-time-slot signal detection on the access waveform to obtain signals of each time slot; detecting current active nodes under each time slot according to the signals of each time slot; if the current active nodes are multiple nodes, performing joint channel estimation according to the front and rear time slots in the at least two time slots of each node to obtain decoding waveforms of each node from a superposition waveform. The method uses a time diversity mechanism, sends the same data at different times by the access node, combines signals of multiple time slots for channel estimation at the receiving end, and even if the signals are seriously affected by fading or interference at some time, reliable signals at other times can supplement information, so that the channel estimation accuracy is improved.

The invention relates to the technical field of communication, in particular to a self-adaptive multi-joint diversity method, system and equipment based on an evaporation waveguide channel and a medium. Meteorological parameters are collected, system diversity parameters are defined, a corrected refractive index profile is constructed, and the height of an evaporation waveguide is determined; based on the corrected refractive index profile, an initial field is calculated through a primary algorithm, the generated initial field is placed in a constructed refractive index profile environment, propagation and output field intensity distribution of an electromagnetic field in a non-uniform medium are solved step by step, RMS time delay spread is calculated through a secondary algorithm, coherent bandwidth is estimated, and the minimum frequency interval is determined based on the coherent bandwidth. Adjusting the minimum frequency interval; the method comprises the following steps: comparing a frequency interval with a minimum frequency interval, adaptively adjusting the frequency interval, respectively simulating space diversity, time diversity and frequency diversity, superposing different diversity, calculating outage probability and fading depth under different diversity, reducing depth fading caused by severe fluctuation of signal amplitude, and improving system availability.

The invention provides a satellite joint channel estimation method, system and device based on CRDSA and a medium, and belongs to the technical field of aerospace communication, and the method comprises the steps: obtaining an access waveform corresponding to a current time frame; the access node uses at least two time slots to send the same service copy packet in the current time frame; performing time slot-by-time signal detection on the access waveform to obtain a signal of each time slot; detecting a current active node under each time slot according to the signal of each time slot; and if the current active node is a plurality of nodes, performing joint channel estimation according to front and back time slots in the at least two time slots of each node, and obtaining a decoding waveform of each node from the superposed waveform. According to the method, a time diversity mechanism is used, an access node sends the same data at different times, so that a receiving end combines signals of a plurality of time slots to perform channel estimation, and even if the signals are subjected to fading or serious interference at some moments, reliable signals at other moments can supplement information, so that the channel estimation accuracy is improved.

This invention relates to the field of wireless channel technology, specifically providing a digital signal processing method based on channel response-maximum ratio combining (CRF). The method includes: inserting training symbols into each frame of a multi-carrier signal; performing channel estimation on each training symbol to obtain the corresponding channel response estimate; estimating the SNR value of each training symbol; calculating normalized weighting coefficients based on the SNR values; and performing a weighted average based on the normalized weighting coefficients and channel response estimates of each training symbol to obtain the overall channel estimation result for the multi-carrier signal. This invention fully utilizes the time diversity characteristics inherent in continuous training symbol transmission, effectively suppressing estimation noise and improving system robustness without significantly increasing computational overhead. Furthermore, this method does not require prior acquisition of channel statistical characteristics, making it particularly suitable for dynamically changing wireless communication environments, achieving a good balance between accuracy, computational efficiency, and practicality.

The application discloses a kind of ultraviolet communication signal processing method and device, it is related to ultraviolet light wireless communication field.The existing kilometer-level communication, error rate is high, communication algorithm is complex.Spread spectrum processing is carried out to the bit sequence to be transmitted, the spread spectrum code obtained by each bit is evenly divided into multiple chip clusters according to the number of time diversity, and the chip clusters corresponding to all bits are interleaved in each time diversity;Pulse shaping is carried out on the interleaved chip clusters under each time diversity, intensity modulation symbols are obtained, and an ultraviolet emitter is driven to emit an ultraviolet light signal;The ultraviolet receiver collects the ultraviolet light signal sequentially adopts threshold sampling strategy, deinterleaving method and despreading processing, and restores the complete bit sequence.It is used to solve the problem of communication error rate and transmission rate.

An OFDM adaptive digital modulation and time domain expansion transmission method based on channel reciprocity belongs to the field of wireless communication technology. The purpose of the present invention is to solve the problem that the existing method cannot fully utilize the subcarrier power and spectrum resources, resulting in the transmission speed of the communication system being limited. The present invention uses channel state information and noise power to perform adaptive modulation, and uses high-order modulation for subcarriers with large channel gain, and uses low-order modulation for subcarriers with small channel gain. In order to make fuller use of subcarrier power and make the transmission rate closer to the theoretical upper limit, the method of the present invention adds more modulation gears to obtain higher resolution. The method of the present invention refers to the equal gain combining method, increases the duration of the symbol to 2 times or more to obtain time diversity gain, so that the same modulation method can obtain multiple transmission speeds, and fully utilizes the subcarrier channel power to make it closer to the theoretical upper limit. The method of the present invention can be applied to the field of wireless communication technology.

The invention discloses a double-frequency bee colony array error multi-domain joint correction system, which belongs to the technical field of radar signal processing, and is characterized in that correction signals of a plurality of correction sources are obtained through time diversity, and each correction source transmits the correction signals to a bee colony array of which the position error exceeds half-wavelength through two carrier frequencies; estimating actual steering vectors of the two carrier frequencies by adopting a simplified SMSWF method; based on the actual steering vectors of the two carrier frequencies, calculating a position error by adopting an equivalent frequency method to obtain an array element position error parameter estimation value; after array element position information is updated by adopting an array element position error parameter estimation value, a position error, a phase error and a communication time delay error are estimated by respectively utilizing receiving signals of two carrier frequencies, and the error joint correction of the bee colony array of which the position error exceeds half wavelength is completed. According to the dual-frequency position error estimation based on the equivalent frequency method, the large error estimation range of the dual-frequency method is fully utilized, the advantage of high error estimation precision of a traditional method is kept, and the error is successfully corrected when the position error exceeds half wavelength.

Embodiments of the present application disclose a signal transmission method, a communication apparatus, a communication system, and a storage medium, which are applied to the technical field of communications and are used to counteract interference or channel fading. The method in the embodiments of the present application comprises: determining an interleaving parameter, the interleaving parameter being used to determine N indexes of N portions of a first data block, and N being an integer greater than or equal to 2; and sending a first signal, the first signal comprising a plurality of first data blocks, wherein portions corresponding to at least two indexes among the N indexes of each first data block are mapped to different time units of the first signal. According to the embodiments of the present application, by means of interleaving among first data blocks, one first data block can be distributed over a plurality of time units in an interleaved manner, thereby effectively counteracting interference or channel fading, obtaining time diversity gain, and improving the reliability of communication transmission.

The invention relates to techniques for NR coverage enhancement. The invention discloses a method for enhancing NR system coverage for wireless devices with limited coverage. Through RRC signaling, DCI, or RAR grant, a serving base station may configure parameters for a coverage limited UE to cause the UE to operate in a coverage enhanced mode. When connecting and communicating with the serving base station, the UE may use the configuration parameters to determine whether to enter the coverage enhancement mode. When PDSCH and PDCCH channels are received, when PUSCH and PUCCH channels are transmitted, and when PUSCH Msg3 is transmitted during random access, the configuration parameters may configure the UE to extend and enhance coverage using both time diversity and frequency diversity. Advantageously, the base station may flexibly and dynamically configure coverage enhancement parameters for the UE to extend the coverage of the UE using time diversity and frequency diversity gains as the UE moves around.

The invention discloses an adaptive joint channel estimation method and device based on a time diversity technology, and the method comprises the steps: carrying out the down-sampling and OFDM demodulation of receiving data, obtaining the frequency domain data of a TB block of a binding time slot, and extracting a first receiving demodulation reference signal of each OFDM symbol in each time slot in the TB block of the binding time slot from the frequency domain data; generating a known sending demodulation reference signal of each OFDM symbol in each time slot in the TB blocks bound with the time slots; according to the frequency domain data, the first receiving demodulation reference signal and a known sending demodulation reference signal, carrying out adaptive joint channel estimation on each partial time slot block in the TB blocks bound with the time slots to obtain estimated sending data of each time slot in the partial time slot blocks; and splicing and decoding the estimated sending data of each time slot in all the partial time slot blocks to obtain sending information of the TB blocks bound with the time slots. The method is adaptive to a flexible time slot system, and joint channel estimation among part of time slots improves the channel estimation precision.

The application discloses a millimeter wave radar human vital sign monitoring method and system based on a diversity mechanism, which comprises a millimeter wave radar having a plurality of transmitting antennas for transmitting millimeter wave signals to the environment and a plurality of receiving antennas for receiving signals reflected by the human body and objects; and a signal processing module for mixing the reflected signals received by the receiving antennas, implementing spatial diversity at the position of the human body to obtain the reflected components of the human body position, estimating echo static components to extract dynamic signals, obtaining dynamic components, implementing time diversity on the echo dynamic components at multiple time points to improve the signal-to-noise ratio, extracting phases and unwrapping the signals after time diversity, performing band-pass filtering and cycle estimation in the time domain to obtain the respiration rate and heart rate of the target. The application utilizes the diversity method to improve the human vital sign monitoring accuracy in a complex environment and at a long distance by comprehensively using the data of multiple antennas and multiple pulses.

The application provides a power distribution network optical fiber fault positioning method and system based on time domain reflection, relates to the technical field of power distribution networks, and comprises the following steps: obtaining optical fiber basic parameter information, generating and phase-modulating an optical carrier signal, dividing the modulated signal into chip sequences and performing orthogonal coding and time domain interleaving modulation to form an enhanced detection signal with space-time diversity characteristics; injecting the signal into an optical fiber and receiving a reflected signal, extracting fault characteristic fingerprint information by using multi-scale wavelet transform and adaptive threshold screening, realizing fault type identification and accurate positioning, and effectively improving fault detection accuracy and positioning precision.

The invention discloses an ultraviolet communication signal processing method and device, and relates to the field of ultraviolet wireless communication. Existing kilometer-level communication is high in error rate and complex in communication algorithm. Performing spread spectrum processing on a bit sequence to be transmitted, averagely dividing a spread spectrum code obtained by each bit into a plurality of chip clusters according to the number of time diversity, and interleaving the chip clusters corresponding to all bits in each time diversity; performing pulse shaping on the chip clusters interleaved under each time diversity to obtain an intensity modulation symbol, and driving an ultraviolet emitter to emit an ultraviolet light signal; and an ultraviolet receiver collects the ultraviolet light signal and sequentially adopts a threshold sampling strategy, a de-interleaving method and de-spreading processing to recover a complete bit sequence. The method is used for solving the problems of communication error rate and sending rate.

The embodiment of the invention discloses a signal transmission method, a communication device, a communication system and a storage medium, which are applied to the technical field of communication and are used for resisting interference or channel fading. The method comprises the steps that interleaving parameters are determined, the interleaving parameters are used for determining N indexes of N parts of a first data block, and N is an integer larger than or equal to 2; a first signal is sent, the first signal comprises the multiple first data blocks, and parts corresponding to at least two indexes in the N indexes of each first data block are mapped to different time units of the first signal. According to the embodiment of the invention, one first data block can be interleaved and distributed on a plurality of time units through interleaving among the first data blocks, so that interference or channel fading can be effectively resisted, time diversity gain can be obtained, and the reliability of communication transmission can be improved.

The present application relates to a kind of modulation and demodulation methods based on time diversity and full carrier index difference chaotic shift keying, the method is suitable for a variety of channels, especially suitable for power line transmission channel, the method is mainly summarized as follows: modulator uses time diversity technology, uses different time to transmit reference information or modulated information multiple times, using index bit to divide the information carrier except reference carrier into two types of carriers activated in turn, and using different modulation signals transmitted in odd and even time to distinguish binary bits.Demodulator obtains reference signal by averaging the signal of different time on reference carrier, and obtains the signal transmitted in odd and even time of each carrier by averaging the signal of odd and even time of information carrier, each information carrier will first distinguish the carrier activated in advance according to the different signal transmitted in odd and even time, so as to recover mapping bit, and then demodulate the corresponding modulation bit on the carrier activated in advance.The present application will improve the anti-noise performance and transmission rate of system.