A space communications study Final report, 15 Sep. 1966 - 15 Sep. 1967

Investigation of signal to noise ratios and signal transmission efficiency for space communication system

Shuttle Ku-band signal design study

Carrier synchronization and data demodulation of Unbalanced Quadriphase Shift Keyed (UQPSK) Shuttle communications' signals by optimum and suboptimum methods are discussed. The problem of analyzing carrier reconstruction techniques for unbalanced QPSK signal formats is addressed. An evaluation of the demodulation approach of the Ku-Band Shuttle return link for UQPSK when the I-Q channel power ratio is large is carried out. The effects that Shuttle rocket motor plumes have on the RF communications are determined also. The effect of data asymmetry on bit error probability is discussed

Theory of phaselock techniques as applied to aerospace transponders

Phaselock techniques as applied to aerospace transponder

Integrated source and channel encoded digital communication system design study

Various aspects of space shuttle communication systems were studied. The following major areas were investigated: burst error correction for shuttle command channels; performance optimization and design considerations for Costas receivers with and without bandpass limiting; experimental techniques for measuring low level spectral components of microwave signals; and potential modulation and coding techniques for the Ku-band return link. Results are presented

SIGNAL: A Ka-band Digital Beam-Forming SAR System Concept to Monitor Topography Variations of Ice Caps and Glaciers

This paper discusses the implementation of an endto- end simulator for the BIOMASS mission. An overview of the system architecture is provided along with a functional description of the modules that comprise the simulator

Optimum and suboptimum frequency demodulation

Optimum and suboptimum linear demodulators for telemetry communication syste

Signal processing for beam position measurement

The spectrum of the signals generated by beam position monitors can be very large. It is the convolution product of the bunch spectrum and the transfer function of the monitor including the transmission cable. The rate of information flow is proportional to the bandwidth and the maximum amplitude rating of monitor complex. Technology is progressing at a good pace and modern acquisition capabilities are such that nearly all the information contained in the spectrum can be acquired with a reasonable resolution [1]. However, the cost of such a system is enormous and a major part of the information is superfluous. The objective of a beam position measurement system is generally restricted to trajectory measurements of a portion of the beam that is much larger than the finer details that can be observed with the bare signal generated by the position monitor. Closed orbit measurements are a simple derivation product of the trajectory and will not be considered further. The smallest beam portion that is of practical interest is one bunch. Hence the maximum frequency is in the order of the bunch repetition rate. Lower frequencies than the bunching frequency may be chosen either to obtain better resolution, either because it is technically easier to accomplish. The sensitivity of beam position monitors degrades quickly at low frequencies. Therefore, signals are selected at some convenient multiple of the bunching frequency and are shifted to so called baseband to match the capabilities of the acquisition system. The task of signal processing is to make a selection among the many frequencies that are available and prepare the signals for acquisition. The signal selection is done by filtering, a vast subject but it will not be treated in this paper. Three signal processing techniques will be examined from the point of view of (amplitude) resolution of a single acquisition of the beam position, dynamic range and operational frequency. They are the following: the homodyne receiver, the phase processor and the logarithmic detector. Baseband techniques are also used in practice and will be briefly mentioned to start

Project apollo. ship-shore communications using radio satellite relay

Requirements for antennas, radio and terminal equipment aboard Apollo communication and tracking ships to communicate with land stations by satellite rela

The response of hard-limiting band pass limiters to PM signals

Output signal to noise ratio of bandpass limiter calculated for phase modulated signa