Title :
Signal-processing receiver for through-the-earth communication
Author :
Raab, Frederick H.
Author_Institution :
Green Mountain Radio Research Co., Colchester, VT, USA
Abstract :
Through-the-earth (TE) propagation subjects a radio signal to considerable attenuation. The uplink signal must, however, be detected in the presence of full-strength atmospheric noise. The author describes an integrated combination of adaptive noise cancellation (ANC), maximum-likelihood detection (MLD), nonlinear processing (NLP), and decision-aided feedback (DAFB) that can be used to combat atmospheric noise in through-the-earth-communication (TEC) systems. Tests with real VLF noise demonstrates improvements in the signal-to-noise ratio (SNR) from 10 to 24 dB. The increased SNR allows higher data rates, greater depth of operation, smaller transmitters, and/or smaller antennas
Keywords :
adaptive signal processing; aircraft communication; error statistics; feedback; maximum likelihood detection; military communication; nonlinear filters; radio receivers; radiofrequency interference; radiowave propagation; telecommunication equipment testing; tropospheric electromagnetic wave propagation; VLF noise; adaptive noise cancellation; atmospheric noise; attenuation; decision-aided feedback; maximum-likelihood detection; nonlinear processing; signal-processing receiver; through-the-earth communication; Attenuation; Feedback; Maximum likelihood detection; Noise cancellation; Radio transmitters; Receivers; Signal to noise ratio; Tellurium; Testing; Transmitting antennas;
Conference_Titel :
Military Communications Conference, 1993. MILCOM '93. Conference record. Communications on the Move., IEEE
Conference_Location :
Boston, MA
Print_ISBN :
0-7803-0953-7
DOI :
10.1109/MILCOM.1993.408594
