Start Date
4-1968 8:00 AM
Description
Present information on missile range planning indicates that serious UHF telemetry coverage problems are likely to occur during re-entry of ballistic vehicles. Flight test experience at VHF has demonstrated that receiving stations experience difficulty in tracking re-entry vehicles under conditions of rapid changes of signal strength caused by combinations of vehicle motion, vehicle antenna pattern, and plasma attenuation 0 Similar but greater variations at UHF coupled with narrow be am widths and reduced sensitivity of re-entry stations portend greater problems at UHFo Conical scan systems may prove inadequate.
Comparisons of similar telemetry systems at VHF and S-band are presented, demonstrating that received signal to noise ratios will be 3 to 9dB below levels presently obtained at VHF for re-entry stations. The narrow antenna beam widths (1° to 3°) will also cause problems in acquisition so that some form of acquisition aid will be required at each station. Omnidirectional antennas currently used in aircraft at VHF will be useless at UHF« Ships and aircraft will require stabilized or compensated antennas. Acquisition of hyper-sonic targets will be a particularly severe problem for aircraft receiving stations .
In addition to defining the re-entry problem, system limitations, and expected effects, this paper also makes recommendations to range planners, operators, and users to minimize or correct the anticipated problems.
Anticipated Problems of Re-Eentry Vehicle Telemetry at UHF
Present information on missile range planning indicates that serious UHF telemetry coverage problems are likely to occur during re-entry of ballistic vehicles. Flight test experience at VHF has demonstrated that receiving stations experience difficulty in tracking re-entry vehicles under conditions of rapid changes of signal strength caused by combinations of vehicle motion, vehicle antenna pattern, and plasma attenuation 0 Similar but greater variations at UHF coupled with narrow be am widths and reduced sensitivity of re-entry stations portend greater problems at UHFo Conical scan systems may prove inadequate.
Comparisons of similar telemetry systems at VHF and S-band are presented, demonstrating that received signal to noise ratios will be 3 to 9dB below levels presently obtained at VHF for re-entry stations. The narrow antenna beam widths (1° to 3°) will also cause problems in acquisition so that some form of acquisition aid will be required at each station. Omnidirectional antennas currently used in aircraft at VHF will be useless at UHF« Ships and aircraft will require stabilized or compensated antennas. Acquisition of hyper-sonic targets will be a particularly severe problem for aircraft receiving stations .
In addition to defining the re-entry problem, system limitations, and expected effects, this paper also makes recommendations to range planners, operators, and users to minimize or correct the anticipated problems.
Comments
No other information or file available for this session.