7 results about "Bandwidth extension" patented technology

Techniques for speech bandwidth extension and denoising. The techniques integrate data-driven artificial intelligence (AI) models specifically trained to be robust to myriad of distortions. The system is capable of producing high-fidelity wideband speech from real-life narrowband inputs. The output is consistently preferred by listeners over the narrowband input, as well as over denoising alone.

This application relates to the field of servo control technology, and in particular to a method, apparatus, and device for extending the bandwidth of a servo system. The method includes: acquiring speed data, current data, and panel gain data of the servo system; identifying speed loop parameters of the servo system based on the speed data, current data, and panel gain data; identifying low-frequency rigid body model parameters based on the speed data; identifying high-frequency flexible model parameters based on the speed data; constructing a speed loop controlled object model based on the low-frequency rigid body model parameters and the high-frequency flexible model parameters; and extending the bandwidth of the servo system based on the speed loop controlled object model and the speed loop parameters. This solves the problems of limited bandwidth extension and low control accuracy in related technologies for servo closed-loop systems.

The method for testing the frequency response parameters of a photodetector first involves constructing a testing device, which includes a dual-carrier light source module, a Mach-Zehnder modulator, the photodetector under test (DUT), a microwave signal source, a data acquisition module, and a control and data processing module. The dual-carrier light source module outputs a dual-carrier optical signal, which is fed into the Mach-Zehnder modulator biased at a specific operating point. The modulator is modulated by the output signal from the microwave signal source connected to the RF drive electrode. The optical signal output from the modulator then enters the DUT to generate a photocurrent signal. The control and data processing module keeps the microwave signal source in an on state. Under this condition, the spectrum analysis module obtains the amplitude information of a specific frequency signal in the output optical signal of the DUT. Analysis and calculation yield the frequency response of the DUT. To further extend the test frequency range, the control and data processing module controls the microwave signal source to be in both on and off states. The spectrum analysis module obtains the amplitude information of a specific frequency signal in the output optical signal of the DUT. Analysis and calculation yield the modulation coefficient of the Mach-Zehnder modulator. Subtracting the modulation response from the amplitude information of the specific frequency signal allows for bandwidth extension testing of the DUT's frequency response.

The present disclosure relates to an anti-aging bandwidth extension device. A circuit for inductive peaking can include a driver, an inverter, a resistor between an output node of the driver and an input node of the inverter, and a switch. For example, a first node of the resistor can be connected to the output node of the driver, and a second node of the resistor can be connected to the input node of the inverter. The switch can be connected between an output node of the inverter and the first node of the resistor. An input node of the driver can correspond to an input node of the circuit, and the output node of the driver can correspond to an output node of the circuit.

This invention relates to the field of front-end active circuit technology, specifically to a three-channel symmetrical broadband high-back-off Doherty power amplifier, comprising a first microstrip line, three equally divided power dividers, a phase compensation network, three input matching networks, a carrier power amplifier, a first peak power amplifier, a second peak power amplifier, a load modulation network, a post-matching network, a DC blocking capacitor, and a second microstrip line. The post-matching network of this invention generates a complex-valued load that varies with frequency at the junction point, compensating for the influence of the peak power amplifier at different offset frequencies, thereby maintaining a small change in the impedance value at the output of the carrier power amplifier and realizing its bandwidth extension function. This solves the problem of high difficulty in implementing broadband design in existing power amplifiers.

The present application relates to the technical field of communications, and provides a signal generation method and an apparatus. In the method, a communication apparatus (such as an access network node or a terminal) acquires a first sequence and a second sequence, performs Fourier transform on the first sequence to obtain a first frequency domain signal, and determines a second frequency domain signal on the basis of the first frequency domain signal and the second sequence. The length of the first sequence and the second sequence is N, N being an integer greater than 1. The second sequence is obtained on the basis of a Zadoff-Chu sequence, and the second frequency domain signal is used for generating a signal to be sent. The method can implement Chirp modulation of the first sequence, and implement bandwidth extension, i.e., a broadband frequency domain signal can be obtained using a small Fourier transform size, thereby improving resource utilization efficiency.

A multi-channel Doherty power amplifier and its bandwidth extension method are disclosed. The power amplifier includes a power divider, an input multiplexer, a main amplification branch, an auxiliary amplification branch, a power combiner, and an impedance matching unit. By constructing multiple frequency complementary branches and introducing an impedance compression network, the power amplifier can continuously cover a wider frequency band, thereby extending the bandwidth. This solves the problem of the requirement for broadband operating mode or multi-frequency reconfiguration mode of energy transmission array in microwave energy transmission systems. The main branch covers the required entire operating bandwidth, and (n-1) auxiliary branches form a frequency complementary relationship to jointly cover the entire operating bandwidth. Each branch uses the impedance compression network to extend its own bandwidth. The main branch and each auxiliary branch completely and continuously cover the operating bandwidth, thereby significantly extending the bandwidth of the Doherty power amplifier.