This paper states the first opened digital railway division communication system which is constructed with Δ M multiplex transmission system and digital division telephone switching system on the toll symetrical cable at Zhengzhou-Luoyang Railway Division .

本文介绍了在郑州&洛阳区段的 长途对称 电缆上开通的我国铁路第一个数字式区段通信系统，它由△M多路复用传输系统和数字式区段电话交换系统构成。