Determinants of Customer Churn: An Empirical Study Of Cellular Subscribers From Saudi Arabia

This research main objective finds the determinants of churn that affect the telecom industry of the Kingdom of Saudi Arabia (KSA). To analyze the churn predictions to retain the customers in the telecom industry, the paper takes factors of churns that create obstacles in the retention of the customers. The variables of the study included switching cost, price, value-added services, and service quality relevant to the telecom industry. The questionnaire was created using adopted items from various studies and was used to collect the data from 315 respondents through non-restricted random sampling. Data reliability and analysis were performed on IBM SPSS®20 software and multiple regressions were applied. The key findings that lower switching costs of cellular network providers significantly lead to customer churn (MNP). This study found that switching costs are not considered a factor if a customer is dissatisfied or innovator in nature to try other companies’ services. Whereas, low service quality, high price structure, and less value-added encourage customers to switch service. The telecom industry should improve its service quality since it is considered one of the most important factors in churning in any industry. This paper would be highly beneficial for the managers of the telecom industry in KSA and other Middle Eastern telecommunication companies

Millimeter-Wave Single- and Dual-Polarized 2x2 MIMO Phased Arrays and In-Situ Over-the-Air System-Level Self-Calibration Techniques for 5G Applications

This dissertation presents two millimeter-wave phased-antenna arrays at 28 GHz for fifth-generation (5G) mobile communication applications as well as techniques for performing in-situ self-test and self-calibration of single- and dual-polarized 5G phased-arrays. First, a scalable 64-element single-polarized transmit/receive phased array is built with 2x2 beamformer chips on a low-cost printed circuit board (PCB). The design emphasis is placed on minimizing the printed circuit board cost, optimizing the cross-polarization performance, and on-grid scalability. The array is capable of scanning +/-50 deg. in azimuth and +/-45deg. in elevation at 29 GHz with cross-polarization rejection better than 20 dB. It achieves an effective isotropic radiated power (EIRP) >50 dBm over a 4 GHz bandwidth from 27 to 31 GHz. Therefore, it is a suitable candidate for Gbps multi-user multiple-input multiple-output (MU-MIMO) base-station applications.Second, a 2x64-element dual-polarized dual-beam phased array for 5G polarization MIMO is built. The phased-array has two 1:16 dual Wilkinson networks and microstrip antennas with rotated feeds for cross-polarization cancellation. The array demonstrates a measured effective isotropic radiated power (EIRP) at Psat of 52 dBm for each beam and is capable of scanning +/-50 deg.in azimuth and +/-25 deg. in elevation with >28-dB cross-polarization rejection. Simultaneous dual-beam operation is demonstrated with near-ideal patterns for each beam. The array demonstrates independent simultaneously transmitted 2x16-quadrature amplitude modulation (QAM) and 2x64- QAM data streams delivering an aggregate maximum data rate of 2x20 and 2x30 Gb/s, respectively.Next, the problem of phased-array calibration is considered. Two calibration techniquesare developed and tested for calibrating single and dual-polarized 5G phased arrays at 28 GHz.The first technique addresses the calibration of single-polarized phased-arrays in a MU-MIMO hybrid beamforming base station system. The procedure, labeled Quad-BIST, enables built-in self-test (BIST) and self-calibration of the arrays in-situ without having to remove the array from the field. Quad-BIST relies on mutual coupling between antennas in neighboring arrays arranged in Quad-fashion to extract the calibration coefficients and perform channel characterization. Quad-BIST was successfully applied to 5G 28 GHz arrays with 4x4 and 8x8 elements in each quadrant. The results show that Quad-BIST predicts the channel states (gain and phase control) with rms errors of 0.2 dB/2 deg. and 0.4 dB/2.5 deg. for the 4x4 and 8x8 quadrants, respectively, as compared to far-field techniques. The relative channel ratios are found to be within rms errors of0.8 dB/7.5deg.. Near-ideal patterns are attained using the quadrant-level calibration for both arrays with side-lobe level’s below -20 dB over scan.The second technique is for the calibration of dual-polarized dual-beam phased arrays. The procedure, labeled (DP-BIST), exploits the mutual coupling between different antennas of orthogonally polarized beams sharing the same aperture to enable in-situ self-calibration and self-test of the phased array channels of each beam. DP-BIST was applied to a 16-element dual-polarized dual-beam linear phased-array at 29 GHz, and predicted the relative channel states (gain and phase control) with rms errors better than 0.3 dB /3 deg. and the relative channel offsets with rms errors of 0.8 dB /6 deg. over a wide-bandwidth. These results demonstrate its feasibility foruse in 5G polarization MIMO phased arrays

Determinants of Customer Churn: An Empirical Study Of Cellular Subscribers From Saudi Arabia

This research main objective finds the determinants of churn that affect the telecom industry of the Kingdom of Saudi Arabia (KSA). To analyze the churn predictions to retain the customers in the telecom industry, the paper takes factors of churns that create obstacles in the retention of the customers. The variables of the study included switching cost, price, value-added services, and service quality relevant to the telecom industry. The questionnaire was created using adopted items from various studies and was used to collect the data from 315 respondents through non-restricted random sampling. Data reliability and analysis were performed on IBM SPSS®20 software and multiple regressions were applied. The key findings that lower switching costs of cellular network providers significantly lead to customer churn (MNP). This study found that switching costs are not considered a factor if a customer is dissatisfied or innovator in nature to try other companies’ services. Whereas, low service quality, high price structure, and less value-added encourage customers to switch service. The telecom industry should improve its service quality since it is considered one of the most important factors in churning in any industry. This paper would be highly beneficial for the managers of the telecom industry in KSA and other Middle Eastern telecommunication companies