2.WCDMA is a 3G network of China Unicom, which evolved from GSM network and is a European standard. WCDMA and GSM are very different, such as access network, frame protocol in the air is completely different, GSM adopts TDMA, while WCDMA adopts CDMA, and the core network is also very different. Both voice service and data service of GSM are core networks in circuit domain. WCDMA voice service takes the circuit domain core network, and data service takes the packet domain core network. The highest rate of GSM data service is only 9.6Kbps, and now the GSM data services used by everyone are basically provided by GPRS and EDGE. The theoretical maximum rate of EDGE is 384Kbps, but it is actually about 30 kbps, while the data service rate of WCDMA is much higher, which can reach 7.2Mbps at present. There is also the frequency and mode of power control. The addressing, transmission power and mobility management of the core network are very different, so it is impossible to make a comprehensive overview here. If you want to know more, you'd better find relevant books. If you just want to know what kind of network you should use, then decide according to your own needs.