scholarly journals A Novel Design of Matched Filter for Digital Receivers

2019 ◽  
Vol 8 (3) ◽  
pp. 6000-6003
Keyword(s):  
Pulse Compression ◽  
Filter Design ◽  
Matched Filter ◽  
Signal To Noise Ratio ◽  
Digital Signal ◽  
Receiver System ◽  
Digital Pulse ◽  
Pros And Cons ◽  
Processing Techniques ◽  
Digital Receivers

In this paper, a brief review regarding introduction to the digital signal processing techniques particularly Digital Pulse Compression and Linear Frequency Modulation involved in matched filtering and some designs being used is presented. Also, the matched filter being developed is discussed by highlighting its pros and cons. The introduction of matched filter in the communication receivers has simplified the design of the system. The matched filter has improved the signal to noise ratio of the receiver system and hence has become an important element in the communication system. This paper also presents the possible challenges; the matched filter design and simulation results in MATLAB have shown satisfactory outputs of the receiver.

scholarly journals Poly-phase signal generation and optimizationof LPI Radar: A new approach

2018 ◽  
Vol 7 (2.6) ◽  
pp. 147
Author(s):  
Jayshree Kamble ◽  
I A Pasha ◽  
M Madhavilatha
Keyword(s):  
Spread Spectrum ◽  
Pulse Compression ◽  
Detection Performance ◽  
Complex Signal ◽  
New Approach ◽  
Frequency Hopping Spread Spectrum ◽  
Phase Signal ◽  
The Difference ◽  
Processing Techniques ◽  
Digital Receivers

Low Probability of Intercept (LPI) Radar own certain positive characteristics make them nearly undetectable by Intercept Receivers. In a battle field, this present a considerable strategic problem. New digital receivers required complex signal processing techniques to detect these types of Radar. This paper address the problem of constructing a new hybrid waveform design using Poly-Phase modulation technique to optimize the detection performance of LPI Radar. Phase coded Pulse compression waveforms using Frequency Hopping Spread Spectrum (FHSS) are designed to evaluate the detection performance of LPI radar in terms of  Discrimination factor (DF).The difference in DF of the Poly-phase coded and Binary phase coded signals is increasing with the increase in the phase values.The effect of noise on Hybrid Poly-Phase waveforms examined using the signal to noise ratios of -10dB,-15dB and -20dB  and extract the parameter necessary for the LPI Radar system. 

Design of Parametric Loudspeaker and Receiver System

2014 ◽  
Vol 909 ◽  
pp. 222-227
Author(s):  
Zi Yu Chen ◽  
Xin Wei Zhang
Keyword(s):  
Signal Processing ◽  
Digital Signal ◽  
Signal Acquisition ◽  
Median Filtering ◽  
Receiver System ◽  
Audible Sound ◽  
Processing Techniques ◽  
Conventional Systems ◽  
Signal Processing Techniques ◽  
Mean Filtering

Parametric loudspeaker systems have been widely used for projecting highly directional audible sound to a specified area. However, the demodulated signal from parametric loudspeaker suffers from high distortion since the nonlinear interaction among primary waves also generate harmonics. In order to reduce distortion, signal acquisition and digital signal processing techniques can be applied at the receiver. In this paper, a parametric loudspeaker and receiver system is designed to reduce distortion using median filtering and mean filtering at the receiver. Compared to conventional systems, the demodulated signal using proposed techniques exhibits lower distortion.

scholarly journals Matched Filter Based Detection over Time Varying Fading Channels with Reduced Complexity

2019 ◽  
pp. 1-6
Author(s):  
Mohd Israil
Keyword(s):  
Signal Processing ◽  
Maximum Likelihood ◽  
Fading Channels ◽  
High Speed ◽  
Matched Filter ◽  
Signal To Noise Ratio ◽  
Digital Signal ◽  
Time Varying ◽  
High Speed Data ◽  
Over Time

Challenges in high speed data transmission technology over time varying fading channels is addressed in this paper. More precisely, the signal processing at the receiver side has to be analyzed for such systems, as it is well known that the mobile radio channels are characterized by frequency selective fast fading is typically introduced error in the received signal. Thus, the performance of the receiver severely degraded because of such factors. Specifically, this paper deals with the detection using a matched filter followed by low weight near maximum likelihood detector (NMLD) for the application of digital signal processing in outdoor vehicular radio environments. Nearly Maximum Likelihood Detection depends on the length of the stored vectors as well as depends on the numbers of the stored vector. In [1] complexity is reduced by reducing the stored vectors, in this paper same NMLD used but the complexity of the matched filter is reduced by some variance. Finally, the bit error rate (BER) is measured with signal to noise ratio.

scholarly journals Mismatched Filter Design using Improved Cuckoo Search Algorithm for Optimum Detection

2019 ◽  
Vol 9 (2S3) ◽  
pp. 93-97
Keyword(s):  
Pulse Compression ◽  
Filter Design ◽  
Matched Filter ◽  
Search Algorithm ◽  
Short Pulse ◽  
Cuckoo Search ◽  
Optimization Techniques ◽  
Radar Signal ◽  
Lévy Flight ◽  
Levy Flight

In radar signal processing pulse compression has been extensively used which solves the problem of maintaining simultaneously high transmit energy of long pulse and large range resolution of short pulse. The concept of pulse compression can be best understood from matched filtering that determines the ratio of peak of the sidelobe to peak value of mainlobe. But the resolution of weak targets from stronger one is difficult due to range sidelobes in the auto-correlation pattern of matched filter. With this idea of reducing these sidelobes, various optimization techniques are used. This paper represents a method to optimize the performance of chaotic sequence using mismatched filter. The optimization completely depends on the design of coefficients of mismatched filter at the receiver side. Here improved cuckoo search method is used instead of Lévy flight cuckoo search with the differential evolution technique to complete the design of cascaded mismatched filter. Finally, improved results are obtained as compared to Lévy flight method of cuckoo search.

A review of self-protection deceptive jamming against chirp radars

2017 ◽  
Vol 9 (9) ◽  
pp. 1853-1861 ◽  
Author(s):  
Samer Baher Safa Hanbali ◽  
Radwan Kastantin
Keyword(s):  
Pulse Compression ◽  
Matched Filter ◽  
Coupling Property ◽  
True Target ◽  
Processing Gain ◽  
Different Types ◽  
Before And After ◽  
Deceptive Jamming ◽  
Pros And Cons ◽  
Self Protection

The well-known range-Doppler coupling property of the chirp radar makes it more vulnerable to different types of deceptive repeater jammers that benefit from the pulse compression processing gain of the radar-matched filter. These jammers generate many false targets that appear before and after the true target. Therefore, the radar cannot distinguish the true target from the false ones. This paper reviews different self-protection repeater jammers and presents their pros and cons, in order to provide a reference for the study of jamming/anti-jamming methods.

scholarly journals Advanced Chirp Transform Spectrometer with Novel Digital Pulse Compression Method for Spectrum Detection

2021 ◽  
Vol 11 (3) ◽  
pp. 960
Author(s):  
Quan Zhao ◽  
Ling Tong ◽  
Bo Gao
Keyword(s):  
Pulse Compression ◽  
Phase Distribution ◽  
Matched Filter ◽  
Time Spectrum ◽  
Intermediate Frequency ◽  
Frequency Resolution ◽  
Digital Pulse ◽  
Sampling Points ◽  
Spectrum Measurements ◽  
Fast Pulse

Based on chirp transform and pulse compression technology, chirp transform spectrometers (CTSs) can be used to perform high-resolution and real-time spectrum measurements. Nowadays, they are widely applied for weather and astronomical observations. The surface acoustic wave (SAW) filter is a key device for pulse compression. The system performance is significantly affected by the dispersion characteristics match and the large insertion loss of the SAW filters. In this paper, a linear phase sampling and accumulating (LPSA) algorithm was developed to replace the matched filter for fast pulse compression. By selecting and accumulating the sampling points satisfying a specific periodic phase distribution, the intermediate frequency (IF) chirp signal carrying the information of the input signal could be detected and compressed. Spectrum measurements across the entire operational bandwidth could be performed by shifting the fixed sampling points in the time domain. A two-stage frequency resolution subdivision method was also developed for the fast pulse compression of the sparse spectrum, which was shown to significantly improve the calculation speed. The simulation and experiment results demonstrate that the LPSA method can realize fast pulse compression with adequate high amplitude accuracy and frequency resolution. Compared to existing digital pulse compression technology, this method can significantly reduce the number of required calculations, especially for measurements of sparse signals.

scholarly journals Software-defined radio-based HF doppler receiving system

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Hiroyuki Nakata ◽  
Kenro Nozaki ◽  
Yuhei Oki ◽  
Keisuke Hosokawa ◽  
Kumiko K. Hashimoto ◽  
...  
Keyword(s):  
Analog Circuits ◽  
Software Defined Radio ◽  
Analog Circuit ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Digital Signal ◽  
Radio System ◽  
Observation Network ◽  
Receiver System ◽  
New System

AbstractHigh-frequency Doppler (HFD) sounding is one of the major remote sensing techniques used for monitoring the ionosphere. Conventional systems for HFDs mainly utilize analog circuits. However, existing analog systems have become difficult to maintain as the number of people capable of working with analog circuits has declined. To solve this problem, we developed an alternate HFD receiver system based on digital signal processing. The software-defined radio (SDR) technique enables the receiver to be set up without the knowledge of analog circuit devices. This approach also downsizes the system and reduces costs. A highly stabilized radio system for both the transmitter and receiver is necessary for stable long-term observations of various phenomena in the ionosphere. The global positioning system disciplined oscillator with an accuracy of $${10}^{-11}$$ 10 - 11 compensates for the frequency stability required by the new receiving system. In the new system, four frequencies are received and signal-processed simultaneously. The dynamic range of the new system is wider (> 130 dB) than that of the conventional system used in HFD observations conducted by the University of Electro-Communications in Japan. The signal-to-noise ratio significantly improved by 20 dB. The new digital system enables radio waves to be received with much smaller amplitudes at four different frequencies. The new digital receivers have been installed at some of the stations in the HFD observation network in Japan and have already captured various ionospheric phenomena, including medium-scale traveling ionospheric disturbances and sudden commencement induced electric field fluctuations, which indicates the feasibility of SDR for actual ionospheric observations. The new digital receiver is simple, inexpensive, and small in size, which makes it easy to deploy new receiving stations in Japan and elsewhere. These advantages of the new system will help drive the construction of a wide HFD observation network. Graphical Abstract

The Effect of Pulse Compression Chirp Parameters on Profilometry Information and Resolution

2018 ◽  
Author(s):  
Zuwen Sun ◽  
Natalie Baddour
Keyword(s):  
Pulse Compression ◽  
Imaging System ◽  
Matched Filter ◽  
Signal To Noise Ratio ◽  
Imaging Systems ◽  
Center Frequency ◽  
Matched Filtering ◽  
Linear Frequency ◽  
Recent Developments ◽  
Correlation Process

Recent developments in imaging systems have seen the implementation of a radar matched-filtering approach. The goal of the imaging system is to obtain information about an unknown object embedded in the system, by controlling the parameters of the input and measuring the response to the known input. The main merit of using matched filtering in imaging systems is the improvement of Signal to Noise Ratio (SNR). However, the correlation process used in matched filtering may result in a loss of resolution. One way to compensate for lost resolution is via pulse compression. Linear frequency modulated sinusoidal waveforms (chirps) have the property of pulse compression after correlation. Hence, both SNR and resolution can be enhanced by matched-filtering and pulse compression with a chirp. However, the theory behind the effect of chirp parameters on resolution is still not clear. In this paper, a one-dimensional theory of matched-filter imaging with a pulse compressed linear frequency modulated sinusoidal chirp is developed. The effect of the chirp parameters on the corresponding signal is investigated, and guidelines for choosing the chirp parameters for resolution considerations are given based on the developed theory and simulations. The results showed that by manipulating the center frequency, bandwidth, and duration of the chirp, the resolution can be easily enhanced.

scholarly journals Comparison of the performance of different radar pulse compression techniques in an incoherent scatter radar measurement

2009 ◽  
Vol 27 (2) ◽  
pp. 797-806 ◽  
Author(s):  
B. Damtie ◽  
M. S. Lehtinen
Keyword(s):  
Adaptive Filtering ◽  
Pulse Compression ◽  
Matched Filter ◽  
Signal To Noise Ratio ◽  
Minimum Mean Square Error ◽  
Radar Signal ◽  
Incoherent Scatter Radar ◽  
Low Snr ◽  
Incoherent Scatter ◽  
Scatter Radar

Abstract. Improving an estimate of an incoherent scatter radar signal is vital to provide reliable and unbiased information about the Earth's ionosphere. Thus optimizing the measurement spatial and temporal resolutions has attracted considerable attention. The optimization usually relies on employing different kinds of pulse compression filters in the analysis and a matched filter is perhaps the most widely used one. A mismatched filter has also been used in order to suppress the undesirable sidelobes that appear in the case of matched filtering. Moreover, recently an adaptive pulse compression method, which can be derived based on the minimum mean-square error estimate, has been proposed. In this paper we have investigated the performance of matched, mismatched and adaptive pulse compression methods in terms of the output signal-to-noise ratio (SNR) and the variance and bias of the estimator. This is done by using different types of optimal radar waveforms. It is shown that for the case of low SNR the signal degradation associated to an adaptive filtering is less than that of the mismatched filtering. The SNR loss of both matched and adaptive pulse compression techniques was found to be nearly the same for most of the investigated codes for the case of high SNR. We have shown that the adaptive filtering technique is a compromise between matched and mismatched filtering method when one evaluates its performance in terms of the variance and the bias of the estimator. All the three analysis methods were found to have the same performance when a sidelobe-free matched filter code is employed.

scholarly journals Software-Defined-Radio Based HF Doppler Receiving System

2021 ◽  
Author(s):  
Hiroyuki Nakata ◽  
Kenro Nozaki ◽  
Yuhei Oki ◽  
Keisuke Hosokawa ◽  
Kumiko Hashimoto ◽  
...  
Keyword(s):  
Analog Circuits ◽  
Software Defined Radio ◽  
Analog Circuit ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Digital Signal ◽  
Radio System ◽  
Observation Network ◽  
Receiver System ◽  
New System

Abstract High-frequency Doppler (HFD) sounding is a major remote sensing technique for monitoring the ionosphere. Conventional systems for HFDs mainly utilize analog circuits. However, existing analog systems have become difficult to maintain as the number of individuals adept at working with analog circuits has declined. To solve this problem, we developed an alternate HFD receiver system based on digital signal processing. The software-defined radio (SDR) technique enables the receiver to be set up without the knowledge of analog circuit devices. This approach also downsizes the system and reduces costs. A highly stabilized radio system for both the transmitter and receiver is necessary for stable long-term observations of various phenomena in the ionosphere. The global positioning system disciplined oscillator with an accuracy of H compensates for the frequency stability required by the new receiving system. In the new system, four frequencies are received and signal-processed simultaneously. The dynamic range of the new system is wider (> 130 dB) than that of the conventional system. The signal-to-noise ratio significantly improved by 20 dB. The new digital system enables radio waves to be received with much smaller amplitudes at four different frequencies. New digital receivers have been installed at some of the stations in the HFD observation network in Japan and have already captured various ionospheric phenomena, including medium-scale traveling ionospheric disturbances and sudden commencement induced electric field fluctuations, which indicates the feasibility of SDR for actual ionospheric observations. The new digital receiver is simple, inexpensive, and small in size, which makes it easy to deploy new receiving stations in Japan and elsewhere. These advantages of the new system will help drive the construction of a wide HFD observation network.

Sign in / Sign up

Export Citation Format

Share Document