This work demonstrates the feasibility of the generation of an RF direct-detection vector signal using optical in-phase/quadrature-phase (I/Q) upconversion. The advantage of the proposed transmitter is that no electrical mixer is needed to generate the RF signal. Therefore, I/Q data of RF signals are processed at baseband at the transmitter, which is independent of the carrier frequency of the ...

This work presents a method for large signal characterization of avalanche photodiode (APD) where measurements were carried out using pulsed RF signal at different DC bias points to extract dispersive parameters of the avalanche photodiode. Pulsed optical excitation on the photodiode were synchronized with the pulsed RF signal using a synchronization circuit and in this way characterization of ...

Deep learning (DL) finds rich applications in the wireless domain to improve spectrum awareness. Typically, DL models are either randomly initialized following a statistical distribution or pretrained on tasks from other domains form of transfer without accounting for unique characteristics signals. Self-supervised (SSL) enables useful representations Radio Frequency (RF) signals themselves eve...

High-field (≥ 3T) MRI provides a means to increase the signal-to-noise ratio, due to its higher tissue magnetization compared with 1.5T. However, both the static magnetic field (B(0)) and the transmit radio-frequency (RF) field (B 1+) inhomogeneities are comparatively higher at higher field strengths than those at 1.5T. These challenging factors at high-field strengths make it more difficult to...

In conventional hybrid beamforming approaches, the number of radio-frequency (RF) chains is bottleneck on achievable spatial multiplexing gain. Recent studies have overcome this limitation by increasing update-rate RF beamformer. This paper presents a framework to design and evaluate such which we refer as agile beamforming, from theoretical practical points view. context, consider impact RF-ch...

In software defined radio systems, placing the analog-todigital converter (ADC) near the antenna part in the block diagram of the receiver is desired to improve the flexibility of the system. The radio frequency (RF) sampling method, in which the received signal is sampled at the RF stage, realizes such structure. The undersampling is a potential method to sample the RF signal using the existin...

Wireless communication receivers work with radio frequency (RF) input signals with a huge dynamic range of 50dB and more. In order to provide the analog-to-digital converters (ADCs) in the receivers with an optimal signal strength, the gains of the RF and IF (intermediate frequency) stages have to be tuned according to the strength of the RF input signal. The RF input signal strength can be est...

Introduction: Interconnection problems between large number of coil elements and the scanner are critical, particularly in high field MRI. Moreover, SNR and RF safety issues are also significant concerns. Recent investigations on the analog optical transmission of MRI signals may alleviate this problem [1-3]. Although traditionally, the transmission of the MR signals is achieved by coaxial cabl...