Accession Number:

AD0600821

Title:

INFORMATION TRANSFER FUNCTIONS THROUGH PLASMAS

Descriptive Note:

Final rept.

Corporate Author:

HALLICRAFTERS CO CHICAGO IL

Personal Author(s):

Report Date:

1964-04-01

Pagination or Media Count:

146.0

Abstract:

The degradation in information content undergone by surveillance and communication signals transmitted through the plasma sheath was calculated for some specific re-entry conditions. A comparative analysis was made for all present day types of modulations assuming a flush mounted slot antenna located near the stagnation point of the re-entry vehicle and operating near, but above, the plasma frequency. The analysis is based on a transfer function which relates the space-time Fourier transforms of the antenna exciting field to the received radiation field. The end results, presented graphically in terms of both error probability and transinformation vs. input signal to noise ratio, are based on the calculated pulse distortion undergone by the signal as it traverses the plasma sheath. The results of the study point out that for the plasma model under consideration the performance of all modulated signals is degraded with the greatest degradation occurring for Amplitude Keying and the least degradation occurring for Phase Shift Keying.

Descriptors:

• *RADIO LINKS
• *INFORMATION THEORY
• *PLASMA SHEATHS
• MATHEMATICAL MODELS
• REENTRY VEHICLES
• DEGRADATION
• SPACE SURVEILLANCE
• MODULATION
• PHASE SHIFT KEYERS
• ELECTROMAGNETIC PULSES
• SLOT ANTENNAS
• STAGNATION POINT
• FUNCTIONS(MATHEMATICS)
• NOISE(RADIO)
• PROBABILITY
• WAVE PROPAGATION
• SIGNALS
• ERRORS
• COMMUNICATION AND RADIO SYSTEMS

Subject Categories:

• Radiofrequency Wave Propagation
• Plasma Physics and Magnetohydrodynamics
• Spacecraft Trajectories and Reentry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE