Technology of 4G is a cellular technology improved from 3G and 2G which provide network with the bandwidth of 75MHz and operated frequency of 1800 MHz. In a process of receiving and sending information signal, 4G system need antenna as the device functioning to send electromagnetic to the air. When information signal is transmitted, there was possibility that the signal weaken which caused by several factors such as air, building wall thickness and weather. Rectangular circular patch array 1x8 microstrip antenna is an antenna functioning as 4G signal strengthens at the frequency of 1800MHz. Antenna was design by using software of CST Studio Suite. From the result of rectangular circular patch array 1x8 microstrip antenna measurement at the frequency of 1800 MHz, it was obtained that the gained was 7.32 dB, VSWR was 1.208, and return loss was -20.3 dB. Performance test of antenna was conducted for 4 Indonesia’s cellular providers namely Telkomsel, Indosat Ooredoo, XL, and 3 in various places. The test result in PNJ telecommunication laboratory showed that the best average value of RSRP from provider of Indosat Ooredoo was-72.9 dBm, the best average value of RSPP from provider of 3 was -70.7 dBm located in Bambon raya, and the best average value of RSPP from provider of XL was -65.2 dBm located in Cibubur.