Radio-Propagation-Measurement-Based Simulations of the Capacity of Multi-User D-MIMO Indirect Path Communication Systems in a Small Cluttered Room at 2, 18, and 28 GHz

Radio communications do not work only in the air and underwater, but also underground. Some applications such as mining and earthquake detection require underground radio devices. This paper reports an assessment of underground radio characteristics for frequency band 97 MHz to 130 MHz. The assessments were performed through an experimental propagation measurement and a mathematical prediction. Both assessments then are compared by using the normalized graph to predict propagation characteristics so that correct link budget for future application can be assisted. The mathematic analysis and measurement results still produce huge errors; achieving 50.33% for frequency 130.762 MHz, 17.58% for 109.818 MHz and 13.38% for 97.335 MHz. Error can be minimized when the ground permittivity is more precise

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Seasonal and Diurnal Variation on Tropospheric Scintillation at Ku-Band in Tropical Climate

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v6i4.10401 ◽

2016 ◽

Vol 6 (4) ◽

pp. 1710

Author(s):

Ibtihal Fawzi Elshami ◽

Jafri Din

Keyword(s):

Communication Systems ◽

Satellite Communication ◽

Elevation Angle ◽

Signal Amplitude ◽

Clear Sky ◽

South West Monsoon ◽

One Year ◽

Tropospheric Scintillation ◽

Propagation Measurement ◽

Ku Band

Tropospheric scintillation is a rapid fluctuation of the received signal amplitude which can cause propagation impairments that affect satellite communication systems operating above 10 GHz. Scintillation data was collected in Equatorial Johor Bahru, Malaysia, based on a one-year Ku-band propagation measurement campaign, utilizing MEASAT-1 Satellite with an antenna elevation angle of 75.61°. This work concentrates on the probability density function (PDF) of diurnal variations of clear sky scintillation variance analyzed on an hourly basis. Besides, seasonal variation of scintillation amplitude has been presented in this paper. From the results, it is concluded that clear sky scintillation variance is likely to occur during morning and afternoon periods. Moreover, clear sky scintillation amplitude of the South-West monsoon shows a relatively higher comparing with others monsoon seasons. Hence, signal attenuation based on seasonal and diurnal information is of great interest for the system designers to appropriately design fade margin.Tropospheric scintillation is a rapid fluctuation of the received signal amplitude which can cause propagation impairments that affect satellite communication systems operating above 10 GHz. Scintillation data was collected in Equatorial Johor Bahru, Malaysia, based on a one-year Ku-band propagation measurement campaign, utilizing MEASAT-1 Satellite with an antenna elevation angle of 75.61°. This work concentrates on the probability density function (PDF) of diurnal variations of clear sky scintillation variance analyzed on an hourly basis. Besides, seasonal variation of scintillation amplitude has been presented in this paper. From the results, it is concluded that clear sky scintillation variance is likely to occur during morning and afternoon periods. Moreover, clear sky scintillation amplitude of the South-West monsoon shows a relatively higher comparing with others monsoon seasons. Hence, signal attenuation based on seasonal and diurnal information is of great interest for the system designers to appropriately design fade margin.

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Propagation Prediction for Rail Communications in Urbanized Areas

2018 Joint Rail Conference ◽

10.1115/jrc2018-6196 ◽

2018 ◽

Author(s):

Todd Ellis ◽

Stephen Weiss

Keyword(s):

Communication Systems ◽

Radio Networks ◽

Radio Propagation ◽

Propagation Models ◽

Train Control ◽

Passenger Rail ◽

System Requirements ◽

Urbanized Areas ◽

Propagation Prediction ◽

Complex Matter

Radio propagation prediction for passenger rail operations using sub-UHF frequencies can be a complex matter. While propagation models and data containing terrain and obstruction information can be used to predict radio coverage, unique methodologies are required to accurately plan and implement rail communication systems. Federally-mandated Positive Train Control (PTC) system requirements rely on consistently available wireless communications, thus the imperative need to accurately design and construct radio networks to fulfill critical requirements.

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