Through-the-earth radio
View Patent ↗A through-the-earth communication system that includes a digital signal input device; a transmitter operating at a predetermined frequency sufficiently low to effectively penetrate useful distances through-the earth; a data compression circuit that is connected to an encoding processor; an amplifier that receives encoded output from the encoding processor for amplifying the output and transmitting the data to an antenna; and a receiver with an antenna, a band pass filter, a decoding processor, and a data decompressor.
1. A through-the-earth communication system comprising:
a digital signal input device;
a transmitter operating at a predetermined frequency sufficiently low to effectively penetrate useful distances through-the earth, receiving said digital signal input and providing said digital input signal to a data compression circuit that is connected to an encoding processor;
an amplifier receiving encoded output from said encoding processor for amplifying said encoded output and outputting said encoded output to an antenna; and
a receiver having an antenna receiving said encoded output followed by a band pass filter being connected to a decoding processor whose output is connected to a data decompressor, said data decompressor providing a decompressed digital signal.
2. The apparatus as described in claim 1 , wherein said digital signal input device is a digital video camera.
3. The apparatus as described in claim 1 , wherein said antenna is a loop antenna.
4. The apparatus as described in claim 1 , wherein said encoding processor operates using quadrature phase shift keying.
5. The apparatus as described in claim 1 , wherein said encoding processor operates using a QAM-16 processor.
6. The apparatus as described in claim 1 , wherein said predetermined frequency is approximately 4 kHz.
7. The apparatus as described in claim 1 , wherein said predetermined frequency is approximately 7 kHz.
8. The apparatus as described in claim 1 , wherein said band pass filter is of the wideband 4-pole elliptic design.
9. The apparatus as described in claim 1 , wherein said antenna is a SQUID detector connected to a flux locked loop.
10. A method of conducting through-the-earth communication comprising the steps of:
inputting an analog signal;
digitizing said analog signal;
compressing said digitized signal;
encoding said compressed digitized signal to encode a predetermined data stream into said compressed digitized signal; and
outputting said encoded compressed digitized signal through an antenna at a predetermined frequency that is sufficiently low to effectively penetrate useful distances through-the-earth as a transmitted signal;
receiving said transmitted signal with an antenna after said transmitted signal has propagated through-the-earth;
converting said transmitted signal from an analog signal to a digital signal;
decoding said digital signal;
decompressing said digital signal; and
outputting said decoded decompressed digital signal.
11. The method as described in claim 10 , where said antenna comprises a SQUID detector followed by a flux locked loop.
12. The method as described in claim 10 , wherein said step of outputting said decoded decompressed digital data further comprises outputting to a speaker.
13. The method as described in claim 10 , wherein said step of outputting said decoded decompressed digital data includes outputting an audio signal.
14. The method as described in claim 10 , wherein said step of inputting an analog signal is accomplished by use of a microphone.