5 词条
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2G wireless network
Second-generation (2G) digital cellular networks used by mobile phones. 2G networks was developed as a replacement for first generation (1G) analog cellular networks, and the GSM standard originally described a digital, circuit-switched network optimized for full duplex voice telephony. This expanded over time to include data communications, first by circuit-switched transport, then by packet data transport via GPRS (General Packet Radio Services) and EDGE (Enhanced Data rates for GSM Evolution or EGPRS).
2G wireless network的贡献者
2G wireless network
鉴栩矗频器
移动通信; 2G wireless network
具有相位检波和频率检波作用的电路。当环路尚未锁定时，使用鉴频部分作为环路辅助电路，它将VCO输出频率与参考标领进行比较而得到一个粗调直流电压（是频差的函数）去控制VCO的频率，使之进入谈相环快捕带；然后由鉴相部分输出直流电压作细调用的直流电压（是相差的函数）使环路迅速锁定。 ...
发射频段
移动通信; 2G wireless network
分配给一种无线通信系统发射所使用的频段。如全接入通信系统（TACS)，其基地台发射频段为935-960MHz，移动台发射频段为890-915MHz。
