Microwave spatial-temporal channel characteristics measured at base station in an urban environment

Author(s):  
H. Masui ◽  
M. Ishii ◽  
K. Sakawa ◽  
H. Shimizu ◽  
T. Kobayashi ◽  
...  
Aviation ◽  
2020 ◽  
Vol 24 (1) ◽  
pp. 42-49 ◽  
Author(s):  
Andrii Grekhov ◽  
Vasyl Kondratiuk ◽  
Svitlana Ilnytska

First built models of Remotely Piloted Air System (RPAS) communication channels based on Wideband Code Division Multiple Access (WCDMA) 3GPP Standard were designed. Base Station (BS) transmission within the Radio Line of Sight (RLoS) and through the satellite using Beyond Radio Line of Sight (BRLoS) was considered. The dependencies of the Bit Error Rate (BER) on the signal-noise ratio for different RPAS velocities and WCDMA сhannel models were obtained. The dependences of the BER on the signal-noise ratio for different levels of satellite transponder nonlinearity were studied. The dependence of the BER on the BS antenna diameter in case of the transponder nonlinearity was analysed. The dependencies for satellite channel characteristics, first obtained taking into account the motion of the RPAS, make it possible to predict the behavior of the communication system in critical conditions.


2021 ◽  
Vol 4 (1) ◽  
pp. 1-9
Author(s):  
Isaac Chukwutem Abiodun ◽  
Joshua Idogho

Propagation path loss exponent is an important component of system design, and knowing the values helps to avoid surprises when the actual service begins. The path loss exponent is known to be critical in establishing the coverage of any new cellular network. Estimating the path loss exponent of any environment requires raising new data sets, which can be accomplished by conducting experiments. With this objective, the present study reports the L-band signal RSS level measurements of 6 GSM base stations in the urban, suburban and rural environments of Ondo and Ekiti States in the Southwestern region of Nigeria. Using a Sony Ericsson TEMS phone monitoring device—connected to a laptop equipped with TEMS software and base station cell reference—and a GPS device, RSS measurements were performed in each sector of the base station up to 1200 m, employing a single sector verification method. The values of path loss exponents were computed from the deduced values of path loss at 50 m intervals up to distances of 1200 m. Close to the base station, the following exponent values were observed—between 2.0 and 3.8 in the urban environment, 2.0 to 2.8 in the suburban environment while for the rural environment, 1.5 to 2.6 we're observed. After the breakpoint distance, higher path loss exponent values of up to 6 was recorded in the urban environment, exponent value of up to 4.3 was observed in the suburban environment and up to 3.5 exponent value in the rural environment. It was also observed that the rural environment presented the longest breakpoint distance of 500 m. The high path loss exponents observed, especially in the urban environment, could cause GSM operators to rethink the margins they have provided. This study is useful for the design of upcoming network systems in these regions and in similar regions.


2021 ◽  
pp. 233-244
Author(s):  
Laszlo Solymar

weThe problem to solve was the frequency allocation and power requirements. A working frequency for a given cluster had to be chosen high enough so that there are enough channels. The power radiated out by the mobile phone had to be large enough to reach the base station and low enough not to cause disturbance in the neighbouring cluster. Also the size of the clusters depended on population density, larger in urban environment, smaller in rural environment. The sudden growth of the number of mobile phones in the period 1994 to 1997 is noted and plotted.


2000 ◽  
Vol 48 (11) ◽  
pp. 1996-2002 ◽  
Author(s):  
E. Piuzzi ◽  
S. Pisa ◽  
M. Cavagnaro ◽  
P. Bernardi

Author(s):  
Shanshan Wang ◽  
Joe Wiart

This paper studies the time and space mapping of the electromagnetic field (EMF) exposure induced by cellular base station antennas (BSA) using artificial neural networks (ANN). The reconstructed EMF exposure map (EEM) in urban environment is obtained by using data from EMF sensor networks, drive testing and information accessible in a public database, e.g., locations and orientations of BSA. The performance of EEM is compared with Exposure Reference Map (ERM) based on simulations, in which parametric path loss models are used to reflect the complexity of urban cities. Then, a new hybrid ANN, which has the advantage of sorting and utilizing inputs from simulations efficiently, is proposed. Using both hybrid ANN and conventional regression ANN, the EEM is reconstructed and compared to the ERM first by the reconstruction approach considering only EMF exposure assessed from sensor networks, where the required number of sensors towards good reconstruction is explored; then, a new reconstruction approach using the sensors information combined with EMF along few streets from drive testing. Both reconstruction approaches use simulations to mimic measurements. The influence of city architecture on EMF exposure reconstruction is analyzed and the addition of noise is considered to test the robustness of ANN as well.


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