The combined effect of broad/partial band jamming on the analysis performance of multi-input/multi-output (MIMO) space time block coding (STBC) systems over Rayleigh fading channel is often neglected in the literature. To this end, this paper investigates the impact of different kinds of jamming on the performance of MIMO STBC systems. Closed form expressions for the bit error probability (BEP) of the performance of binary phase shift keying (BPSK) STBC communication system over Rayleigh fading channel under the impact of both partial band and broad-band jamming for different number of transmitting and receiving antennas are presented. Computer simulations are provided to validate the theoretical developments. It has been found that the performance of such systems is severely deteriorated in the presence of strong jamming power (with a signal to jamming power ratio less than − 10dB) and the worst scenario occurs in the presence of broad-band jamming.
Interference is one of the major concerns in using the global positioning system (GPS) for civilian and military applications. In this paper, a new classification of different interference signals is presented. This classification is based on the interference signal's bandwidth and the GPS correlator coherent integration time.The new classification simplifies the evaluation of the interference effect on the GPS receiver correlator output for different interference signals such as: continuous wave interference (CWI), narrowband interference (NBI), partial band interference (PBI), and broadband interference (BBI). Novel closed form analytical expressions for the GPS receiver correlator output power for CWI, NBI, PBI, and BBI are derived. The effect of the GPS correlator coherent integration time, the interference bandwidth, and the interference frequency error are also investigated under the impact of these types of interference.
Vulnerability of global positioning system (GPS) receiver to interference signals is one of the major issues of many applications, as the satellite navigation signal has a very low power under the noise floor level. To this end, pulse interference (PUI) may cause severe performance degradation to the GPS receivers. This study analyses the PUI effect on the GPS receiver correlator output. Novel and more accurate closed-form analytical expressions are derived for the PUI power at the correlator output. The post-correlation carrier-to-noise ratio for the GPS L1 coarse acquisition (C/A) signal is analytically derived in the presence of PUI and additive white Gaussian noise. In order to simplify the derived analytical expressions, a classification is done depending on the relationship between the C/A code spectrum and the PUI spectrum. Several PUI parameters were varied such as interference frequency, pulse period and duty cycle to investigate the influence of these parameters on the GPS correlator output.
This paper investigates spectrum shaping in ultrawideband (UWB) communication systems in order to introduce spectral nulls to mitigate the impact of in-band narrowband interference (NBI) signals in the IEEE 802.15.3a UWB channel models. It has been seen that due to the restraint on their transmission power levels, UWB systems unavoidably suffer from the interference caused by the coexisting systems, making it extremely difficult to maintain adequate signal-to-noise-andinterference ratio (SNIR) levels. To this end, we propose the use of a "Digital Delay Filter" scheme, which is designed to generate a spectral null at the frequency being used by existing narrowband devices. Our results show that NBI can be effectively suppressed with the use of such null steering scheme, therefore improving the robustness of UWB systems to NBI. Also, it will be shown that the proposed delay filter outperforms a perfectly tuned notch filter.
Mohamed S. Abdel-Latif EW Department, M. T. C. mnna3000@yahoo.com Automatic modulation recognition is very important for communication intelligence applications such as signal interception for satellite communications, civil authority, surveillance and threat analysis. Automatic digital modulation recognition is a system that automatically classifies the modulation type of the intercepted signal. This paper presents a method for the automatic recognition of digital modulations without a priori knowledge of the signal parameters. This algorithm works at low signal to noise ratio and get nearly to 100 % of correct classification percentage at 0 dB which is effective in Electronic warfare and communication surveillance applications. This method can recognize common single-carrier modulated satellite communication signals such as M-ary phase-shift keying, M-ary quadrature amplitude modulation and M-ary amplitude phase shift keying which used in DVB-S2. This algorithm is performed by a sequential steps to blindly classify the signal using PSD of instantaneous amplitude, kurtosis and HOS (cumulants).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.