VLF ground wave telephone equipment

Abstract

A VLF ground wave telephone equipment in VLF band (20-300 KHz) is composed of user extensions, switch, ground wave telephone power amplifier-transmitter, ground coupled transmitting network and power supply. Said user extensions consist of emitter, receiver and dialing circuit. Said ground coupled transmitting network is composed of feed back line, impedance converter, transmitting antennas, high-voltage (10KV) power transmission line, and grounding electrode networks. Its advantages are developing new frequency resource, high anti-interference power, stable and reliable signals, no blind region in transmission, low cost and high security and compatibility.

Description

technical field [0001] The invention belongs to the technical field of communication, and in particular relates to a very low frequency ground wave telephone device. Background technique [0002] At present, my country's rural communication mainly uses wired telephone equipment and wireless telephone equipment. Wired telephone equipment needs to set up dedicated poles and dedicated lines to send telephone signals to users. This kind of wired telephone network construction consumes a lot of manpower, material resources, and financial resources. It costs hundreds of thousands of yuan to build a telephone network in a township. After the network is built, it is easily damaged by natural forces and man-made damage. There are many external line failures and heavy maintenance tasks. . Although wireless telephone equipment does not need poles and wires, it must build tall transmitting antenna towers, which are transmitted directly by air waves, which are easily blocked by mountai...

AI Technical Summary

Problems solved by technology

This kind of wired telephone network construction consumes a lot of manpower, material resources, and financial resources. It costs hundreds of thousands of yuan to build a telephone network in a township. After the network is built, it is easily damaged by natural forces and man-made damage. There are many external line failures and heavy maintenance tasks.

Although wireless telephone equipment does not need poles and wires, it must build tall transmitting antenna towers, which are transmitted directly by air waves, which are easily blocked by mountains and deep valleys, with many blind spots, low coverage in mountainous areas, and crowded air radio frequency channels. severe interference

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