scholarly journals RF photonic front-end integrating with local oscillator loop

2014 ◽  
Vol 22 (4) ◽  
pp. 3918 ◽  
Author(s):  
H. Yu ◽  
M. Chen ◽  
H. Gao ◽  
S. Yang ◽  
H. Chen ◽  
...  
Author(s):  
Tran Van Hoi ◽  
Ngo Thi Lanh ◽  
Nguyen Xuan Truong ◽  
Nguyen Huu Duc ◽  
Bach Gia Duong

<p>This paper focuses on the design and implementation of a front-end for a Vinasat satellite receiver with auto-searching mechanism and auto-tracking satellite. The front-end consists of a C-band low-noise block down-converter and a L-band receiver. The receiver is designed to meet the requirements about wide-band, high sensitivity, large dynamic range, low noise figure. To reduce noise figure and increase bandwidth, the C-band low-noise amplifier is designed using T-type of matching network with negative feedback and the L-band LNA is designed using cascoded techniques. The local oscillator uses a voltage controlled oscillator combine phase locked loop to reduce the phase noise and select channels. The front-end has successfully been designed and fabricated with parameters: Input frequency is C-band; sensitivity is greater than -130 dBm for C-band receiver and is greater than -110dBm for L-band receiver; output signals are AM/FM demodulation, I/Q demodulation, baseband signals.</p>


2013 ◽  
Vol 834-836 ◽  
pp. 1140-1144 ◽  
Author(s):  
Yong Tai Chen ◽  
Chang Jing Sun ◽  
Bin Zang ◽  
Long Cheng ◽  
Jing Tang ◽  
...  

Phase noise and spurious signals of local oscillator will affect the performance of short-wave receiver. The structure of receiver's front-end part based on DDS is introduced to realize a high-performance local oscillator of short-wave receiver. Then measures were taken to improve the LO's performance, including using external directly frequency multiplier as DDS' clock to improve the purity of frequency spectrum, tracking filter to degrade harmonics and gain control circuit to remain constant amplitude in the desired frequency range. At last, test results show that the above-mentioned measures improve the receiver's performance.


1991 ◽  
Vol 131 ◽  
pp. 42-46
Author(s):  
G.H. Tan

AbstractThe Westerbork Synthesis Radio Telescope will be equipped with new front ends. These front ends will cover 8 frequency bands in the range from 250 MHz to 8.6 GHz. For the frequency bands above 1.2 GHz the sensitivity of the instrument will be drastically improved. Two independent local oscillator systems make it possible to observe in two frequency bands simultaneously.


2014 ◽  
Vol 926-930 ◽  
pp. 2503-2507
Author(s):  
Wen Kai Liu ◽  
Peng Wang ◽  
Jian Cui

RF front-end is an important part of the communication system. It realizes the functions such as low noise amplifier application, filtering and mixing, completes the conversion between the IF signal and the RF signal, and ensures effective communication system flexibility and versatility. In the paper, according to the superheterodyne structure, a receiver RF front-end has been designed. The total gain of the link circuit is more than 100 dB, with 50 dB AGC range, the center frequency is 750 MHz with 100MHz bandwidth, local oscillator (LO) signal with frequency 935MHz is generated by PLL and the stability is-82dBc/Hz@1KHz.


2020 ◽  
Vol 643 ◽  
pp. A126
Author(s):  
Laurent Pagani ◽  
David Frayer ◽  
Bruno Pagani ◽  
Charlène Lefèvre

Aims. Radio observing efficiency can be improved by calibrating and reducing the observations in total power mode rather than in frequency, beam, or position-switching modes. Methods. We selected a sample of spectra obtained from the Institut de Radio-Astronomie Millimétrique (IRAM) 30-m telescope and the Green Bank Telescope (GBT) to test the feasibility of the method. Given that modern front-end amplifiers for the GBT and direct Local Oscillator injection for the 30 m telescope provide smooth pass bands that are a few tens of megahertz in width, the spectra from standard observations can be cleaned (baseline removal) separately and then co-added directly when the lines are narrow enough (a few km s−1), instead of performing the traditional ON minus OFF data reduction. This technique works for frequency-switched observations as well as for position- and beam-switched observations when the ON and OFF data are saved separately. Results. The method works best when the lines are narrow enough and not too numerous so that a secure baseline removal can be achieved. A signal-to-noise ratio improvement of a factor of √2 is found in most cases, consistent with theoretical expectations. Conclusions. By keeping the traditional observing mode, the fallback solution of the standard reduction technique is still available in cases of suboptimal baseline behavior, sky instability, or wide lines, and to confirm the line intensities. These techniques of total-power-mode reduction can be applied to any radio telescope with stable baselines as long as they record and deliver the ONs and OFFs separately, as is the case for the GBT.


Author(s):  
Tran Van Hoi ◽  
Ngo Thi Lanh ◽  
Nguyen Xuan Truong ◽  
Nguyen Huu Duc ◽  
Bach Gia Duong

<p>This paper focuses on the design and implementation of a front-end for a Vinasat satellite receiver with auto-searching mechanism and auto-tracking satellite. The front-end consists of a C-band low-noise block down-converter and a L-band receiver. The receiver is designed to meet the requirements about wide-band, high sensitivity, large dynamic range, low noise figure. To reduce noise figure and increase bandwidth, the C-band low-noise amplifier is designed using T-type of matching network with negative feedback and the L-band LNA is designed using cascoded techniques. The local oscillator uses a voltage controlled oscillator combine phase locked loop to reduce the phase noise and select channels. The front-end has successfully been designed and fabricated with parameters: Input frequency is C-band; sensitivity is greater than -130 dBm for C-band receiver and is greater than -110dBm for L-band receiver; output signals are AM/FM demodulation, I/Q demodulation, baseband signals.</p>


Electronics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 291
Author(s):  
Fang Han ◽  
Jian Gao ◽  
Xiaoran Li ◽  
Zhiming Chen

A four-channel receiver front-end is designed and implemented for interference- and jamming-robust global navigation satellite system (GNSS) in a 0.18-μm CMOS technology. The front-end consists of four identical RF-to-IF signal paths including low-noise amplifiers (LNAs), mixers and IF amplifiers. In addition, it also includes a phase-locked loop (PLL), which synthesizes the local oscillator (LO) signal, and a serial peripheral interface (SPI) for parameter adjustment. To improve the interference and jamming robustness, a novel linearity improvement technology and LO duty cycle adjustment method are applied in LNA and mixer design, respectively. The receiver achieves a gain of 40 dB, an input-referred third-order intercept point (IIP3) of −8 dBm and a jammer-to-signal power ratio (JSR) of 72 dB under 1.8-V and 3.3-V supply, while occupying a 4 × 5 mm2 die area including the electrostatic discharge (ESD) I/O pads.


2015 ◽  
Vol 7 (3-4) ◽  
pp. 307-315 ◽  
Author(s):  
Marc van Heijningen ◽  
Jeroen A. Hoogland ◽  
Peter de Hek ◽  
Frank E. van Vliet

The front-end circuitry of transceiver modules is slowly being updated from GaAs-based monolithic microwave integrated circuits (MMICs) to Gallium-Nitride (GaN). Especially GaN power amplifiers and T/R switches, but also low-noise amplifiers (LNAs), offer significant performance improvement over GaAs components. Therefore it is interesting to also explore the possible advantages of a GaN mixer to enable a fully GaN-based front-end. In this paper, the design-experiment and measurement results of a double-balanced image-reject mixer MMIC in 0.25 μm AlGaN/GaN technology are presented. First an introduction is given on the selection and dimensioning of the mixer core, in relation to the linearity and conversion loss. At the intermediate frequency (IF)-side of the mixer, an active balun has been used to compensate partly for the loss of the mixer. An on-chip local-oscillator (LO) signal amplifier has been incorporated so that the mixer can function with 0 dBm LO input power. After the discussion of the circuit design the measurement results are presented. The performance of the mixer core and passive elements has been demonstrated by measurements on a test-structure. The mixer MMIC measured conversion loss is <8 dB from 6 to 12 GHz, at 1 GHz IF and 0 dBm LO power. The measured image rejection is better than 30 dB.


Sign in / Sign up

Export Citation Format

Share Document