scholarly journals Sensitivity Criterion and Law on a Navigation Receiver under Single Frequency Electromagnetic Radiation

2021 ◽  
Vol 12 (1) ◽  
pp. 204
Author(s):  
Mei Li ◽  
Guanghui Wei
Keyword(s):  
Electromagnetic Radiation ◽  
Electromagnetic Interference ◽  
Continuous Wave ◽  
Density Ratio ◽  
Single Frequency ◽  
Initial Value ◽  
Step Size ◽  
Testing Method ◽  
Noise Density ◽  
Working Frequency

To objectively assess the anti-electromagnetic interference ability of the navigation receiver, the sensitivity criterion of a certain type of navigation receiver is tested under single-frequency continuous wave electromagnetic radiation with an optimized testing method. The experimental results show that it is difficult to guarantee the accuracy of the measurement value of the sensitivity level by using the carrier-to-noise density ratio (C/N0) as the sensitivity criterion, but the initial C/N0 of each satellite can be used as the basis for identifying whether the navigation system has recovered from the interference. The experimental error is dramatically decreased when the sensitivity criterion of “the sensitive phenomenon appears within the first 4 s, and the loss of positioning lasts for 30 s” is employed, the variable interference power step size is adopted and all of the satellites C/N0 are required to recover to the initial value after an interference. The critical interference field intensity error can be controlled within 1 dB by using all these measures. The sensitivity law of the navigation receiver is the same under different working signal intensities. It is significantly sensitive in the working frequency bandwidth. It is also quite sensitive in −11.5 MHz~55.5 MHz of the frequency offset range. The positive sensitive bandwidth is about 5 times that of the negative sensitive bandwidth.

scholarly journals Prediction Model of In-Band Blocking Interference under the Electromagnetic Radiation of Dual-Frequency Continuous Wave

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Kai Zhao ◽  
Guanghui Wei ◽  
Yaping Wang ◽  
Xiaodong Pan
Keyword(s):  
Electric Field ◽  
Electromagnetic Radiation ◽  
Continuous Wave ◽  
Prediction Models ◽  
Single Frequency ◽  
Prediction Errors ◽  
Test Results ◽  
Dual Frequency ◽  
Communication Station ◽  
Peak Value

Two hypotheses for the blocking effect mechanisms under the electromagnetic radiation are presented, and the corresponding dual-frequency interference prediction models are proposed, which can be used to predict the working state of equipment under the condition that the single-frequency susceptibility is known. By taking a radar and a communication radio as the EUT, the experiments of dual-frequency continuous wave electromagnetic radiation are designed and carried out to verify the prediction models. The test results show that the sensitive bandwidth of blocking interference effect for the tested radar and the communication station is consistent with their working bandwidth, respectively. By substituting the test data into the proposed prediction models, the prediction errors of the models are less than 13%. Moreover, it can be found that the tested radar is more sensitive to the peak value of electric field, and the tested communication station is more sensitive to the effective value of electric field.

scholarly journals Research on Continuous Wave Electromagnetic Effect in Swept Frequency Radar

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xue Du ◽  
Guanghui Wei ◽  
Hongze Zhao ◽  
Xiaodong Pan
Keyword(s):  
Field Strength ◽  
False Alarm ◽  
Electromagnetic Interference ◽  
Continuous Wave ◽  
Single Frequency ◽  
Electromagnetic Effect ◽  
Interference Field ◽  
Electromagnetic Environment ◽  
Front End ◽  
Interference Mechanism

In order to establish the prediction model of radar equipment in multisource complex electromagnetic environment, the blocking effect and false alarm interference effect caused by single-frequency CW (continuous wave) electromagnetic interference on typical radar equipment are studied. Taking a certain sweep radar as the research object, the equivalent injection test of EMI (electromagnetic interference) is carried out. Based on the theory of radar front door coupling, the interference mechanism of EMI to radar receiver RF front end is revealed, and the variation law of blocking target and false alarm target level is analyzed. The results show that, under the single-frequency CW-EMI, the target echo level decreases with the increase of the interference field strength, and the false alarm level increases with the increase of the interference field strength. The blocking jamming sensitive bandwidth is about f 0 ± 200   MHz , and the false alarm jamming sensitive bandwidth is about f 0 ± 80   MHz .

scholarly journals A Local Oscillator Phase Compensation Technique for Ultra-Wideband Stepped-Frequency Continuous Wave Radar Based on a Low-Cost Software-Defined Radio

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 780
Author(s):  
Kazunori Takahashi ◽  
Takashi Miwa
Keyword(s):  
Software Defined Radio ◽  
Initial Phase ◽  
Continuous Wave ◽  
Low Cost ◽  
Local Oscillator ◽  
The Other ◽  
Ultra Wideband ◽  
Single Frequency ◽  
Wave Radar ◽  
Stepped Frequency

The paper discusses a way to configure a stepped-frequency continuous wave (SFCW) radar using a low-cost software-defined radio (SDR). The most of high-end SDRs offer multiple transmitter (TX) and receiver (RX) channels, one of which can be used as the reference channel for compensating the initial phases of TX and RX local oscillator (LO) signals. It is same as how commercial vector network analyzers (VNAs) compensate for the LO initial phase. These SDRs can thus acquire phase-coherent in-phase and quadrature (I/Q) data without additional components and an SFCW radar can be easily configured. On the other hand, low-cost SDRs typically have only one transmitter and receiver. Therefore, the LO initial phase has to be compensated and the phases of the received I/Q signals have to be retrieved, preferably without employing an additional receiver and components to retain the system low-cost and simple. The present paper illustrates that the difference between the phases of TX and RX LO signals varies when the LO frequency is changed because of the timing of the commencement of the mixing. The paper then proposes a technique to compensate for the LO initial phases using the internal RF loopback of the transceiver chip and to reconstruct a pulse, which requires two streaming: one for the device under test (DUT) channel and the other for the internal RF loopback channel. The effect of the LO initial phase and the proposed method for the compensation are demonstrated by experiments at a single frequency and sweeping frequency, respectively. The results show that the proposed method can compensate for the LO initial phases and ultra-wideband (UWB) pulses can be reconstructed correctly from the data sampled by a low-cost SDR.

High-power, continuous-wave, single-frequency, all-periodically-poled, near-infrared source

2012 ◽  
Vol 37 (24) ◽  
pp. 5049 ◽  
Author(s):  
Kavita Devi ◽  
S. Chaitanya Kumar ◽  
M. Ebrahim-Zadeh
Keyword(s):  
High Power ◽  
Near Infrared ◽  
Continuous Wave ◽  
Single Frequency ◽  
Periodically Poled ◽  
Infrared Source

scholarly journals Stable, 12 W, continuous-wave single-frequency Nd:YVO_4 green laser polarized and dual-end pumped at 880 nm

2011 ◽  
Vol 19 (7) ◽  
pp. 6777 ◽  
Author(s):  
Jianli Liu ◽  
Zhiyong Wang ◽  
Hong Li ◽  
Qin Liu ◽  
Kuanshou Zhang
Keyword(s):  
Continuous Wave ◽  
Green Laser ◽  
Single Frequency

scholarly journals ТЕКСТИЛЬ ДЛЯ ЗАХИСТУ ВІД ЕЛЕКТРОМАГНІТНОГО ВИПРОМІНЮВАННЯ

2019 ◽  
Vol 134 (3) ◽  
pp. 48-61
Author(s):  
О. П. Кизимчук ◽  
С. І. Арабулі ◽  
В. І. Власенко
Keyword(s):  
Electromagnetic Radiation ◽  
Electromagnetic Interference ◽  
Scientific Literature ◽  
Radiation Shielding ◽  
Production Methods ◽  
Textile Materials ◽  
Basic Production ◽  
Materials Used

Analysis  of  existing  textile  materials  used  for  electromagnetic  radiation  shielding,  their systematization, and basic production methods are the main goals of this review. Methodology. The review of scientific literature and the systematization of the results in the field "textile materials for electromagnetic interference" are the main methods used for this research.

Continuous-wave, single-frequency intracavity singly resonant optical parametric oscillator at 1.5-\mum wavelength

2009 ◽  
Vol 7 (3) ◽  
pp. 244-245
Author(s):  
刘建丽 Jianli Liu ◽  
李永民 Yongmin Li ◽  
刘勤 Qin Liu ◽  
王垚廷 Yaoting Wang ◽  
张宽收 Kuanshou Zhang
Keyword(s):  
Optical Parametric Oscillator ◽  
Continuous Wave ◽  
Parametric Oscillator ◽  
Single Frequency ◽  
Optical Parametric ◽  
Resonant Optical Parametric Oscillator

Progress on High-Power Low-Noise Continuous-Wave Single-Frequency All-Solid-State Lasers

2021 ◽  
Vol 48 (5) ◽  
pp. 0501002
Author(s):  
张宽收 Zhang Kuanshou ◽  
卢华东 Lu Huadong ◽  
李渊骥 Li Yuanji ◽  
冯晋霞 Feng Jinxia
Keyword(s):  
Solid State ◽  
High Power ◽  
Continuous Wave ◽  
Low Noise ◽  
Single Frequency ◽  
Solid State Lasers

Investigation of Hundred-Watt All-Solid-State Continuous-Wave Single-Frequency 1064 nm Laser

2017 ◽  
Vol 44 (6) ◽  
pp. 0601007 ◽  
Author(s):  
郭永瑞 Guo Yongrui ◽  
卢华东 Lu Huadong ◽  
苏静 Su Jing ◽  
彭堃墀 Peng Kunchi
Keyword(s):  
Solid State ◽  
Continuous Wave ◽  
Single Frequency
Sign in / Sign up

Export Citation Format

Share Document