A DSP-Based Impulsive Noise Generator for Test Applications

2009

As part of a larger project to assess the risk associated with the deployment of wireless equipment in electricity substations the BER performance of IEEE 802.11b and IEEE 802.11a in the presence of impulsive noise has been investigated. Middleton class A noise model is used to simulate impulsive noise environment and Simulink is used to simulate the WLAN physical layer. The observed degradation in performance is compared with that due to additive white Gaussian noise.

2008 International Wireless Communications and Mobile Computing Conference, 2008

a laboratory test to assess the impact of impulsive noise on the performance of WLAN equipment is described. The test is put in the context of a larger programme of work to assess the performance ands reliability of wireless equipment subject to partial discharge noise in high voltage electricity supply substations. The character of partial discharge and WLAN technology are briefly reviewed. The laboratory test methodology is reported and some preliminary results are presented. A related forthcoming field-trial for tests of WLAN equipment in a 275/400 kV air-insulated substation is briefly described.

IEEE Transactions on Vehicular Technology, 2002

Noise amplitude distribution measurements relevant to satellite-mobile radio systems are reported. The rationale for the measurements is outlined and the choice of measurement parameters justified. The measurement equipment and measurement methodology are described in detail. Results characterizing the elevation angle distribution of impulsive noise are presented for rural, suburban, and urban environments and also for an arterial road (U.K. motorway) carrying high density, fast moving traffic. Measurements of the levels of impulsive noise to be expected in each environment for high-and low-elevation satellite scenarios using appropriate antenna configurations are also presented.

ursi.org

This paper presents the results of a study covering measurement of the wide band impulsive noise present in DVB-T and UMTS radio channels. The measurements have been taken in an urban environment in the frequency band corresponding to channel 69 for DVB-T and the lower channel in the UMTS band. To analyse the impulsive noise it has been modelled as a pulse train where the pulse amplitude, pulse duration and elapsed time between pulses are considered random variables. Results show that noise pulses appear in noise bursts. The pulse amplitudes can be very high compared to the thermal noise and even compared to the signal levels specified for both systems. However, pulse duration is small compared to the system symbol interval.

IEEE Transactions on Electromagnetic Compatibility, 2000

The trend of electronic systems toward higher integration and higher performance has also brought new challenges to the design of radio transceivers. The decrease of switching times accompanied by the increase of clock speeds, data rates, and interconnection speeds contribute to improve the overall system performance. At the same time, they also affect wireless communications due to an increment of the emissions of electromagnetic radiation. In this paper, we show that the statistics of the baseband components of the noise follow the K-distribution. The one-sided version of this distribution has been derived before as a model for the envelope of sea echo in radar and sonar, however, we show here that its two-sided version can also be used to model the interference noise that affects a transceiver located inside a computer platform. The model shows good agreement with experimental measurements. Also, a closed-form expression of the bit error rate (BER) and some bounds are computed.

IEEE Journal on Selected Areas in Communications, 1993

Absfracf-This paper presents the results of average and impulsive noise measurements inside several office buildings and retail stores. The noise measurement system operated at 918 MHz, 2.44 GHz, and 4 GHz with a nominal 40 MHz 3 dB RF bandwidth. Omnidirectional and directional antennas were used to investigate the characteristics and sources of RF noise in indoor channels. Statistical analyses of the measurements are presented in the form of peak amplitude probability distributions, pulse duration distributions, and interarrival time distributions. Simple first-order mathematical models for these statistical characterizations are also presented. These analyses indicate that photocopiers, printers (both line printers and cash register receipt printers), elevators, and microwave ovens are significant sources of impulsive noise in office and retail environments.

IEEE Access, 2017

We present results from the first phase of our measurement campaign designed to provide information on the current radio noise levels. Our focus is to understand if the increasing number of users and devices with inbuilt low-cost wireless transceivers has increased the noise levels considerably. We also study the stochastic properties of contemporary radio noise. In the literature, it is almost universally assumed that radio noise is well modeled by a white Gaussian stochastic process, and we study how often deviations from this baseline are found. Our measurement approach is able to capture frequency-and time-domain data with very high accuracy in diverse indoor and outdoor locations, providing a broad overview of the influence the environment has on noise and man-made interference. The results cast doubts on the widely used assumptions that consider man-made interference as an extra AWGN component over thermal noise floor. We also discuss the issue of modeling the measured radio noise and we explain the major research challenges for future work.

2015

In wireless communication system thermal noise is one of the noise that detected at the receiver. Thermal noise (Johnson Noise) exists in all resistors and results from the thermal agitation of free electrons therein by the temperature.This paper starts with an introduction onhow temperature appears on the receiver and thermal noise on thereceiver. The major contribution factor to thermal noise power and RMS voltage is also discussed analytically. The CDMA modem is used as a subject to study thermal noise in wireless communication system.

Advanced Information Systems

The subject matter is analysis and evaluation of efficiency of noise-like signals in wireless information transmission systems. The aim is quality of service improvement for mobile subscribers, due to communication channel multiplexing using complex signal-code structures. The objective is development of a systemic view of the technology of information transmission using ultra-short pulse signals focusing on main phenomena that arise at different stages of signal transmission in a wireless information transmission system. The methods use dare sequential analysis, simulation modeling and digital signal coding. The following results have been obtained. An antenna design featuring an expanding slit has been proposed for effective emission and reception of noise-like signals. A method for controlling radiation pattern of such antenna array has been developed. Gaussian Monocycle coding of information with time position-pulse modulation has been justified to be used as a noise-like signal. It has been shown that for the organization of independent channels in one frequency band, it is practical to use a system of orthogonal codes, e.g. Walsh sequence. Due to accumulation of pulses of a useful information signal in the receiver correlator, significant increase in signal-to-noise ratio becomes possible, which enables information transmission over a wide frequency range well below the noise level. As a result, a systematic understanding of the technology of information transmission using ultra-short pulse signals in wireless information transmission systems is developed and a quantitative evaluation of the efficiency of the proposed technical solutions is provided. Conclusion. The use of noise-like signals in wireless information transmission systems provides for high data transmission rates with high interference immunity and tapping protection communication channel. The ability to operate with low emitted power and the high penetrability of noise-like signals through various obstacles, for example, walls, allow meeting the requirements for electromagnetic compatibility and ensuring stable communication in conditions of multipath propagation of radio waves. These circumstances form the basis for the development and implementation of information transfer technology using noise-like signals when designing office networks.