arXiv subjects

Bogdan Uljasz

Publications and source records attributed to Bogdan Uljasz.

3 recordsLinked to original sources

arXiv2018

BER measurements in the evaluation of operation correctness of VSAT modem traffic interfaces

This paper presents using bit error rate (BER) measurements to evaluate operation correctness of traffic (input-output) interfaces in modem of very small aperture terminal (VSAT). Such functional tests are carried out, for example, when purchasing communication equipment for armed forces. Generally, available standards do not describe measurement procedures in this area. In this case, accredited laboratories should develop dedicated assessment methodologies. In this paper, we show the methodology for the VSAT modems, which is based on the BER measurements.

cs.IT↗

arXiv2018

Comparison of angular spread for 6 and 60 GHz based on 3GPP standard

In an urban environment, a multipath propagation is one of the basic phenomena affecting a quality of received signals. This causes dispersions in time and angular domains. Basic parameters describing these dispersions are the rms delay spread and rms angle spread, respectively. The delay spread is related to a frequency of the transmitted signal and the nature of the propagation environment. In this paper, we show a mutual relationship between the time and angular dispersions in the received signal. The obtained simulation results present a comparison of the described dispersions for two different frequencies. In this case, the multi-elliptical propagation model and standard model developed by 3GPP are the basis for the simulation analysis of new communication system solutions.

cs.IT↗

arXiv2018

Evaluation of angular dispersion for various propagation environments in emerging 5G systems

Angular dispersion is the effect of a multi-path propagation observed in received signals. An assessment of this phenomenon is particularly important from the viewpoint of emerging fifth generation (5G) communication systems. In these systems, using the beam-forming and massive multiple-input multiple-output antenna arrays are planned. This phenomenon also has a negative impact on direction finding and older generation communication systems used in an urban environment. In this paper, we present the angular dispersion evaluation for various propagation environments based on simulation studies. This analysis is carried out for different environment types defined in the 3GPP standard model for a selected frequency. In this case, the angular spread is determinated based on the power angular spectrum. This parameter is the basis for the influence evaluation of the propagation environment on the received signal angular dispersion.

cs.IT↗