13 results about "Path gain" patented technology

The application belongs to the technical field of integrated circuits, and particularly relates to a fourth-order delta-sigma modulator design method and system based on passive stacking. The application cascades a quantizer after a third-order active loop filter, and couples capacitors in parallel on the plate of a capacitor array of the quantizer. Sampling and quantization are performed in each cycle. The quantizer quantizes the output of the current loop filter. After quantization, the plate of the capacitor array naturally forms a residual voltage and stores the coupling capacitors. In the noise injection phase of the next cycle, the quantization error stored in the coupling capacitors in the last cycle is injected into the input end of the quantizer through charge redistribution, is weighted and superimposed with the intermediate signal to form the input voltage of the quantizer, and the main path attenuation coefficient and the coupling path gain coefficient are obtained through charge conservation analysis. A gain compensation factor is preset in the front-stage active integrator to offset signal attenuation, and the capacitor ratio is optimized to realize fourth-order noise shaping. The application does not require additional active circuits, has small area and low power consumption, and improves the signal-to-noise ratio.

The present application relates to the technical field of non-line-of-sight target detection, and particularly relates to a RIS-assisted FMCW radar non-line-of-sight target DOA estimation method, which comprises the following steps: constructing a scene model of RIS-assisted FMCW radar non-line-of-sight target detection; performing DOA estimation on the target to calculate the angle information of the target relative to the radar; and proposing an alternating direction multiplier method based on a path gain maximization criterion to optimize the RIS phase shift matrix parameters, which can significantly enhance the received signal strength and quality by regulating the electromagnetic wave propagation environment, maximize the equivalent channel gain of the target path, effectively suppress the multipath interference and noise, make the real direction information of the target in the received signal more prominent, not only significantly improve the signal-to-noise ratio, but also ensure that the structure of the received signal covariance matrix is highly matched with the model relied on by the high-resolution estimation algorithm of the subspace class, improve the accuracy, resolution and reliability of the angle estimation, and improve the real-time performance.

A receiver includes an analog to digital converter circuit, a phase detector circuit, a digital loop filter circuit, a phase interpolator circuit, and a bias adaption circuit. The analog to digital converter circuit is configured to convert a first signal into a second signal according to a clock signal. The phase detector circuit is configured to detect a phase of the second signal to generate a phase detection signal. The digital loop filter circuit is configured to scale the phase detection signal with a proportional path gain coefficient and a bias value to generate a third signal. The phase interpolator circuit is configured to generate the clock signal according to the third signal. The bias adaptation circuit is configured to accumulate the phase detection signal to generate the bias value.

The invention relates to the technical field of integrated circuits, in particular to a voltage-controlled oscillator gain calibration method and circuit, and the method comprises the steps: obtaining a first frequency control word and a second frequency control word, generating a first control voltage signal, and outputting a second control voltage signal; an error control signal is generated by comparing the numerical values of the digital signals to adjust the second control voltage signal until voltage locking is achieved; calculating the ratio of the frequency offset corresponding to the second frequency control word to the absolute value of the voltage difference to obtain a gain value of the voltage-controlled oscillator; associatively storing the gain value and the first frequency control word in a lookup table; and querying the lookup table according to the real-time first frequency control word in the phase modulation process to obtain a gain value so as to adjust the gain matching of the modulation path. The influence of frequency, process, voltage and temperature changes on the gain of the voltage-controlled oscillator is compensated through closed-loop calibration, gain matching of a low-pass path and a high-pass path in the phase modulation charge pump phase-locked loop is maintained, phase errors are restrained, and the reliability of a communication link is improved.

The invention provides a wireless communication link high-fidelity simulation method for a high-dynamic Internet of Vehicles, which comprises the following steps of: performing channel modeling by using a channel simulation platform according to an input network layout, a terminal track, a propagation scene and an antenna mode to generate a time-varying channel coefficient; accurate modeling is carried out on key physical phenomena such as multipath propagation, Doppler frequency shift, path gain and propagation time delay in the Internet of Vehicles, and high-fidelity simulation of channel dynamic change characteristics in a high-mobility scene is realized; a transmitter class object, a receiver class object and a channel class object are constructed based on an object-oriented thought, a plurality of processing modules such as QAM modulation, multi-carrier modulation, pilot frequency design, channel estimation and equalization, frequency offset correction and the like are supported, and good transportability and expansibility are achieved. According to the invention, high-fidelity Internet of Vehicles communication system simulation is realized, a communication transceiver signal processing flow is included, and an efficient fidelity verification platform is provided for design and test of an Internet of Vehicles communication protocol and algorithm.

The application relates to a dynamic power supply system and control method for a radio frequency power amplifier, which comprises an envelope detection module, an envelope mapping module, an S-class power amplifier, a mapping establishment module and a feedback demodulation module. The envelope mapping module converts the envelope of a transmitting signal into a control voltage according to a mapping relationship, and the S-class power amplifier efficiently generates a dynamic power supply voltage proportional to the control voltage to supply power to the radio frequency power amplifier, thereby improving the efficiency of the radio frequency power amplifier. The envelope mapping relationship is provided by the mapping establishment module. The mapping establishment module combines and adjusts the transmitting path gain and the maximum power supply voltage, so that the radio frequency power amplifier works in a predetermined compression state, and the envelope mapping relationship is established according to the constant gain criterion. The application can provide dynamic power supply for the radio frequency power amplifier under a large working bandwidth and a complex working environment, effectively improve the efficiency of the radio frequency power amplifier, and has excellent spurious and near-carrier noise suppression capability.

The application discloses a distributed radar-communication integration method based on time delay-Doppler joint modulation, comprising the following steps: acquiring a radar-communication integration signal received by a receiving end, extracting a communication signal echo and a radar signal echo from the radar-communication integration signal; acquiring target time delay, path gain and Doppler information by using a cross-correlation method according to the radar signal echo; demodulating the communication signal echo by using a turbo iterative maximum ratio combining algorithm to obtain communication data in a time delay-Doppler domain grid; and positioning and measuring the speed of the target by using a chan method according to the target time delay and Doppler information, so as to obtain a target positioning and speed measuring result.

The invention relates to an RIS phase shift optimization and beamforming method and system based on computable channels, and the method comprises the steps: calculating channels from a base station to an RIS and from the RIS to a user based on the positions of the base station, the RIS and the user; establishing an optimization problem by using a maximum channel capacity criterion, and constraining a channel in combination with a position; a Riemannian manifold optimization algorithm and a Riemannian conjugate gradient algorithm are adopted to optimize a phase shift matrix of an RIS reflection unit, and optimal RIS reflection path adjustment is carried out; and the base station and the user obtain an all-digital beam forming matrix by using the adjusted RIS reflection path, and design a hybrid beam forming matrix to optimize the spectrum efficiency. In the invention, the base station calculates the azimuth angle and the path gain of the transmitted beam according to the RIS and the user position, after feedback, the intelligent reflecting surface adjusts the reflecting angle according to the fed-back angle information, and meanwhile, hybrid beam forming is designed at the base station end and the user end, so that the spectrum efficiency of the system can be effectively improved, and the millimeter wave transmission bottleneck is solved.

The invention discloses a wireless communication transmission performance analysis method based on an intelligent reflecting surface. The processing method comprises the following steps: creating a wireless communication model in simulation software or a real environment; extracting multipath components such as path gain through a ray tracing technology; performing channel modeling and completing channel reconstruction according to the multipath component; respectively carrying out accuracy analysis on the time delay and the azimuth angle from time and space angles; and carrying out transmission performance analysis on the wireless communication system in combination with the intelligent reflecting surface. According to the method, the resolution (namely accuracy) of the multipath component (MPC) can be effectively improved, the gain of the intelligent reflecting surface (RIS) on the signal transmission efficiency is proved, the transmission performance of the wireless communication signal can be comprehensively evaluated, and a scientific basis is provided for the optimization design and transmission performance analysis of a wireless communication system.

The application discloses a near-field CSI distributed estimation method for wideband XL-MIMO. Firstly, a center LPU estimates path delay parameters of a center subarray channel, other LPUs quickly extrapolate path delay parameters of other subarray channels, and the estimation results are transmitted to a CPU. Then, based on near-field beam oblique vision and parameter symmetry characteristics caused by a large array and a large bandwidth, the CPU fuses the delay parameters estimated by different subarrays, decouples and independently estimates near-field channel parameters, including angle, distance and range parameters. Then, the CPU transmits the estimated near-field channel parameters back to the LPUs, each LPU independently estimates path gain of the subarray channel, and finally, the LPUs transmit the estimated path gain to the CPU, and then reconstruct the full-dimensional wideband near-field channel. The method overcomes the problems of too large CSI acquisition and calculation complexity and low reconstruction accuracy in the large array and large bandwidth scene.

The invention relates to a channel estimation method of a multi-user communication system based on RIS assistance. The channel estimation method of the multi-user communication system based on RIS assistance comprises the following steps: each user in the communication system sends a pilot signal in sequence, and a base station receives the pilot signal; the base station processes the pilot signal, scans and matches an antenna array vector corresponding to the angle of the RIS channel of the base station, and finds a common support row set; channel estimation from each user to a base station is solved; scanning and matching a planar antenna array vector corresponding to the angle of the RIS user channel, and solving a column support set of each user; solving a path gain coefficient of each base station RIS user; and reconstructing a cascade channel matrix of the users to obtain cascade channel estimation between each user and the base station. The channel estimation method of the multi-user communication system based on RIS assistance has the advantages that the method does not depend on idealized hypotheses and is closer to actual application scenes.

The invention belongs to the technical field of integrated circuits, and particularly relates to a design method and system of a fourth-order delta-sigma modulator based on passive stacking, a quantizer is cascaded behind a third-order active loop filter, a coupling capacitor is connected in parallel on an upper pole plate of a capacitor array of the quantizer, and sampling and quantization phases of each period are connected in parallel. The quantizer quantizes the output of the current loop filter, and after quantization is finished, an upper polar plate of the capacitor array naturally forms residual voltage and stores the residual voltage in the coupling capacitor; in the noise injection phase of the next period, the quantization error of the previous period stored in the coupling capacitor is injected into the input end of the quantizer through charge redistribution, the quantization error and the intermediate signal are subjected to weighted superposition to form the input voltage of the quantizer, and a main path attenuation coefficient and a coupling path gain coefficient are obtained through charge conservation analysis. A gain compensation factor is preset in the front-stage active integrator to offset signal attenuation, and the capacitance ratio is optimized, so that fourth-order noise shaping is realized. An additional active circuit is not needed, the area is small, the power consumption is low, and the signal-to-noise ratio is improved.

This invention relates to the field of learning path recommendation and discloses a personalized learning path recommendation system based on multimodal data analysis. The system includes a multimodal data acquisition module, a state credit assessment module, a path topology reconstruction module, and a modal transcoding and recommendation module. By collecting environmental signals and operational behavior signals to extract features, the system quantifies the instantaneous attenuation of each sensory channel to generate instantaneous cognitive load impedance data. It calculates the Euclidean distance between the knowledge node content source impedance data and the cognitive load impedance data, establishes impedance mismatch penalty term data, and uses it as a negative feedback factor to generate a reconstruction transition probability matrix. The system solves for the sequence with the maximum global path gain in the reconstruction matrix as the prefetched path and triggers multimodal material decoupling transcoding in real time when impedance mismatch exceeds the limit. This invention can dynamically adjust the recommended path according to the individual's cognitive state and achieve sensory load balancing compensation, effectively avoiding cognitive overload and improving learning efficiency.