#TITLE_ALTERNATIVE#

• Main Author: Wahyu Nadir ( NIM : 232 99 003), Adi
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/7036
• Institution: Institut Teknologi Bandung

Abstract: <br /> <br /> <br /> <br /> <br /> Power control (PC) is a mechanism that controls the received power in cellular system. This mechanism will make the received signal quality for all users at a relative equal value. Each user is represented by one mobile station (MS). Without PC, the received quality for the MS near to the base station (BS) will be bigger than the ones that are far. This is because the received power at the BS is linearly inversed with the square of distance. This phenomenon is called near-far effect <br /> <br /> <br /> <br /> <br /> Power control is dMded into two methods, power based and Signal to Noise Ratio (SNR) based. Power based will make the received power in the BS at a relative same value, meanwhile SNR based will equalize the received quality. The quality mentioned is the SNR value, which is the ratio of wanted signal power and the total of unwanted received power plus Additive White Gaussian Noise (AWGN). <br /> <br /> <br /> <br /> <br /> The principle of power control is to order the MS to raise its power level if the received value is lower than the target. In the other hand, if the received value is higher than the target, the MS should lower its transmit power. This process is used for power based and SNR based. <br /> <br /> <br /> <br /> <br /> This research compares the power based and SNR based PC in one indoor cell system that uses Code Division Multiple Access (COMA). Besides that, we will offer the optimum parameters that will be used in the system. From the research, power control for indoor condition is the same as the others. The effect of reflections and obstruction is the ones that differs them. <br /> <br /> <br /> <br /> <br /> When we add another MS in the cell, power based will lower its average quality at about 1-2 dB, meanwhile in SNR based, the average transmit power will be raised about 1-2 dB, and vice versa. <br /> <br /> <br /> <br /> <br /> Dynamic power range used in indoor should be raised from IS-95 standard, which is 86 dB to 116 dB. This is used to accommodate the indoor path loss that is not very big. Using the standard value will contribute instability to the system for several cases. <br /> <br /> <br /> <br /> <br /> Initial MS transmit power value will also affect the initial stability of the system, specifically when there is an addition to the number of users in the cell. For best performance, we should use the minimum initial transmit power. From the research, we took the value from the ERP minus dynamic power range, which is -110.15 dBW. <br /> <br /> <br /> <br /> <br /> From the simulation, we got average outage for the system, which are 0,47761 % for 9,6 Kbps, and 0,84821 % for 14,4 Kbps voice rate. The higher the voice rate, the higher the number of users, or the smaller the SNR target, the outage that we got will be much more bigger. <br />