Showing papers on "Modulation index published in 1978"
TL;DR: In this paper, a CW dye laser was converted into a train of 0.5 ns pulses by frequency modulation and passage through a near-resonant atomic vapor delay line of Na.
Abstract: The 5890 A output from a CW dye laser was converted into a train of 0.5 ns pulses by frequency modulation and passage through a near-resonant atomic vapor delay line of Na. The theory of the process is discussed in both the time and frequency domains. Using a modulation index of 120 at a frequency of 17.8 MHz, we obtained values for the temporal compression ratio and intensity enhancement of 112 and 14, easily the largest that have been reported.
53 citations
TL;DR: A theory for the performance of Costas loops in the presence of residual carrier as a function of the key system parameters is established and this theory is applied toward predicting the performance degradation in the PM mode (relative to PSK operation) of the Shuttle S -band uplink.
Abstract: When a Costas loop is operated in a PM mode, such as on the Space Shuttle Orbiter S -band uplink during the time when both data and a ranging subcarrier are linearly modulated on the carrier, and if the data modulation index is less than \pi/2 , the loop must reconstruct its carrier reference from an input signal whose carrier component is not completely suppressed. This paper establishes a theory for the performance of Costas loops in the presence of residual carrier as a function of the key system parameters and applies this theory toward predicting the performance degradation in the PM mode (relative to PSK operation) of the Shuttle S -band uplink. The corresponding performance of the ranging channel is also given as a function of these same system parameters.
6 citations
Patent•
13 Apr 1978
TL;DR: In this article, the need for tracking servo at the reproduction is eliminated by phasemodulating a carrier signal by a video signal at a specified modulation index and recording the modulated wave.
Abstract: PURPOSE:In a magnetic disc, the need for tracking servo at the reproduction is eliminated by phase-modulating a carrier signal by a video signal at a specified modulation index and recording the modulated wave.
2 citations