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Ultra-Wideband Radar Receivers
Published in James D. Taylor, Introduction to Ultra-Wideband Radar Systems, 2020
James D. Taylor, Elizabeth C. Kisenwether
Superheterodyne receivers convert a higher frequency signal into a lower frequency (intermediate frequency) which has the same modulation. Lower, single center frequency, narrowband amplifiers are easier to build and keep working properly, and the modulating signal bandwidth is usually a small portion of the intermediate frequency. Superheterodyne receivers can detect impulse signals if they are strong enough, e.g., lightning, strong radio frequency energy sources, etc. Figure 10.13A shows a basic superheterodyne receiver. We will show how to estimate the detectable signal impulse level later.
Radar Electronic Warfare
Published in Habibur Rahman, Fundamental Principles of Radar, 2019
Superheterodyne receivers: These receivers have the advantage of high sensitivity and good frequency resolution. Unfortunately, this type of receiver has a poor probability of intercept. This condition is much worse if the emitter is also frequency-agile or frequency-hoping. One method of mitigating this problem is to employ acousto-optic Bragg cell receivers, which utilize the Bragg refraction of optical-guided beams by surface acoustic-wave (SAW) filters to perform spectral analysis. Pulse width, frequency agility, and speed in searching are unreliable parameters that are inherent.
Measurement of system parameters
Published in Geoff Lewis, Communications Technology Handbook, 2013
Image channel interference. The superheterodyne (superhet) receiver deliberately beats the wanted signal together with one generated from its own internal local oscillator. The difference signal, or intermediate frequency, is then processed instead of the wanted signal. However, as shown in Fig. 18.5(b), there are two frequencies f1 and f2 that give rise to this effect: one is the wanted channel and the other a mirror image of it about the local oscillator frequency. This image is also known as a second channel, the wanted channel being the first.
A reconfigurable wireless superheterodyne receiver for multi-standard communication systems
Published in International Journal of Electronics, 2023
Qing Wang, Yongle Wu, Yue Qi, Weimin Wang
At present, there are many mainstream wireless receiver architectures for communication equipment. Such as superheterodyne receiver architecture (Dan et al., 2019), zero intermediate frequency (zero-IF) receiver architecture (T. Wang et al., 2019), and low intermediate frequency (low-IF) receiver architecture (Zhang et al., 2018). Among them, the superheterodyne receiver architecture is widely used in wireless communication systems. The superheterodyne receiver has many advantages, such as excellent frequency selection characteristics, good interference suppression, and a large dynamic range. The zero-IF receiver is simple and easily integrated, but noise and linearity are not as good as the superheterodyne receiver. The cost of the low-IF receiver is high because it needs a high-performance Analog-to-Digital Converter. According to our design requirements, we finally choose the superheterodyne structure to form the proposed receiver.