The analysis of ACS spec. in WCDMA receiver systems

In this paper, we analyze the ACS specification and the reasons for 33dB in WCDMA systems, which is the minimal required value of ACS. The tests of the practical RF receive circuits is done under the condition that the 3 center frequencies are 2110 MHz, 2140 MHz and 2170 MHz respectively. The result is the level of the modulated interference signal is between -48 dBm and -42 dBm @ BER = 0.001, and the amplitude margin is between 3.9 dB and 9.2 dB, when the frequency offset from carrier is ± 5 MHz. Obviously, it satisfies the -52 dBm requirements of 3GPP.