说明：  常规的单载波调制技术在带宽有限的测井电缆上的低传输速率制约着成像测井技术的发展。在分析测井 电缆传输特性和 OFDM 技术原理的基础上 ,设计了一种基于 OFDM 技术的测井电缆高速数据传输系统 ,并介绍了 基于 OFDM 技术的测井电缆高速数据传输系统的参数设计和工作原理 ,给出了不同长度测井电缆上的测试结果。 电缆实测结果表明 ,在 7 000 m长的测井电缆上 ,基于OFDM 技术的测井电缆高速数据传输系统可获得900 kbit / s 以上的数据传输速率和低于 5E28 的误码率。当变压器的接入模式为 Mode2II时 ,系统最高的数据传输速率可达到 1. 1 Mbit/ s。
(To solve t he low data t ransmission rate problem in t he conventional single car rier mod2 ulation met hod for logging cable and enhance t he data t ransmission rate , a new data t ransmission system with high data t ransmission rate for logging cable is propo sed , which is based on t he Or2 t hogonal Frequency Division Multiplexing (OFDM) technology. The working principle of OFDM modem and t he procedure of data t ransmission system are al so presented and lot s of test s are car2 ried out on logging cables with different lengt hs. It is verified that t he data t ransmission rate can reach 900 kbit/s on 7 000 meter s logging cable wit h bit er ror rate (BER) lower t han 5E28 , and t he maximum data t ransmission rate is 1. 1 Mbit/s under Mode2II of t he t ransformer .)