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Abstract-The aim of this paper is to introduce the measurement method for challenging Non-Line of Sight (NLOS) conditions in mobile networks. The need to develop the measurement method appeared LTE (Long Term Evolution) uplink (UL) performance with different antenna technologies when receiving NLOS signal in field tests. Many challenges appeared during the study. This paper introduces the challenges and presents solution.

This article has two main objectives. First, it describes the practical challenges of field trials and proposes a developed test method. Secondly, the test method is used to compare uplink performance with different antenna technologies when user equipment does not have a line of sight to the evolved Node B. Both passive and active antenna configurations were used in the performance evaluation. Modern cellular networks have high demands for capacity, reliability, and availability. The verification of a network's configuration and technological features is essential to guarantee network performance, and the performance of a network must be verified by laboratory testing or field trials; such trials produce experimental knowledge of technology features and configurations. Technological and environmental factors must also be considered before performing mobile network field-testing. Our work showed that moving user equipment produces more reliable and repeatable results than measurements with stationary user equipment. Our antenna configuration comparison study revealed that in the uplink direction, active antenna system beam control could significantly increase the uplink capacity in non-line-of-sight conditions. Index Terms-2-and 4-way RX diversity, AAS, field trial, horizontal beamforming, non-line-of-sight environment, MIMO, uplink capacity improvement, vertical beamforming.

This study presents the usage of unmanned aircraft for site survey and antenna pattern measurements in-situ in mobile networks. The site survey is one part of the verification and optimization process of the network operator. Mobile network operators' responsibility is to ensure the broadly available, reliable network series that are essential for customer experience. Technically that means mobile network coverage of the desired area without holes and with good capacity. The operator performs network planning in order to optimize coverage and capacity. It is essential to know the antenna pattern to plan and design an effective and efficient mobile network. Antenna manufacturers provide antenna radiation patterns measured in the standard anechoic chamber. Understanding how real site implementation differs from the laboratory measurements is also crucial. This study focuses on developing in-situ antenna measurements for the antenna patterns recorded in the laboratory. The evaluation of antenna radiation patterns in a real environment will provide additional information about what kind of effect the antenna site mast, installation, and antenna performance parameters will have on the theoretical radiation pattern.

The unmanned aircraft systems (UAS) are commonly used for aerial photography, express delivery for packets or video monitoring. The UAS technology can help responding to the growing demands of the frequency monitoring by national radiocommunication authorities (NRAs). This article presents a practical usage trial of an unmanned aircraft for monitoring the spectrum usage and finding the interference location. The monitoring of spectrum usage is one part of the NRAs' process for guarantee user compliance with radio license conditions. Finding illegal or malfunctioning transmitters is a challenging task especially in urban environment, due to multi-path propagation conditions. This study focuses on practical assessment of the method for determining accurate location of radio frequency interference sources from the buildings using the UAS technology. The practicability of the UAS technology usage in spectrum monitoring activities was under the evaluation. This study showed promising results that UAS with the measurement equipment setup suits NRAs' as a tool for mobile monitoring on the air.