Accession Number : ADA288909

Title :   Electromagnetic Spectrum Occupancy Study of a Potential Transmitter Site for the HF Active Auroral Research Program (HAARP).

Descriptive Note : Interim rept. May-Jun 93,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Goldstein, Joseph A. ; Kennedy, Edward J. ; McGown, Monroe Y.

PDF Url : ADA288909

Report Date : 30 SEP 1994

Pagination or Media Count : 50

Abstract : This report presents the results of measurements conducted by the Naval Research Laboratory in May and June 1993. The purpose of the measurements was to ascertain the radio frequency occupancy in the immediate vicinity of the proposed High Frequency Active Auroral Research Program (HAARP) facility to be constructed in the Gakona, Alaska area. The HAARP facility will consist of a large planar array of antennas excited by phased high power transmitters operating in the lower portion of the HF band (2.8 to 8 MHz). The existing electromagnetic spectrum usage in the vicinity of Gakona was measured in order to assess the potential for electromagnetic interference problems arising from the HAARP facility. The measurements covered the frequency spectrum from 2 MHz to 1000 MHz. Data was collected for a period of 17 days in May and early June 1993. There are a large number of users in the HF band and data shows a normal diurnal pattern of energy increase in the lower portion of the band in the nighttime hours. The number of users decreases with increasing frequency because the propagation path at higher frequencies is dependent upon line-of-sight signal paths. Gakona is a very rural area and is separated by hilly terrain from surrounding residential and commercial activities. Above the HF bend, the most prominent signal identified is a 152 MHz transient signal that saturates the signal path of our measurement apparatus. The signal is so strong that it produces harmonics throughout the measurement band and distorts the display of the data. Another strong feature that is sometimes observed is a 450 MHz signal.

Descriptors :   *AURORAE, *RADIO TRANSMITTERS, *ELECTROMAGNETIC SPECTRA, HIGH FREQUENCY, ELECTRON DENSITY, HARMONICS, ELECTROMAGNETIC WAVE PROPAGATION, ELECTROMAGNETIC RADIATION, ELECTROMAGNETIC INTERFERENCE, AMPLITUDE, RADIO WAVES, RADIOFREQUENCY, SPECTRUM ANALYZERS.

Subject Categories : Radiofrequency Wave Propagation
      Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE