| 单词 | PDC (Personal Digital Cellular) |
| 释义 | PDC (Personal Digital Cellular) Previously known as Japanese Digital Cellular (JDC). A Japanese standard for a 2G digital cellular radio system operating in the 800 MHz, 900 MHz, and 1400 MHz frequency bands. PDC employs frequency division duplex (FDD) to support bidirectional communications with the downlink in the 810–826 and 1429–1453 bands and the uplink in the 940–956 and 1477–1501 bands. PDC derives 1,600 carriers of 25 kHz, and employs time division multiple access (TDMA) to derive three channels per carrier.The channel bit rate is 42 kbps, with the modulation method being /4 differential quaternary phase shift keying (/4 DQPSK). Full-rate voice encoding is at 9.6 kbps using vector sum excited linear predictive coding (VSELP) and half-rate at 5.6 kbps using code excited linear prediction (CELP). PDC has not found acceptance outside Japan, with the exception of a few Asian countries under Japanese economic influence. PDC is being phased out in Japan, in favor of cdma2000. See also 2G, band, carrier, cdma2000, cellular radio, CELP, channel, digital, downlink, FDD, frequency, modulation, /4 DQPSK, TDMA, uplink, and VSELP. |
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