Investigate optimum way of adding wideband capability and recommend a design for modification of one government furnished AM baseband demultiplexer

The hardware design and implementation and test results are described of the accommodation of two wideband channels, 8 kHz DSB/QDSB located at 44 kHz and 16 kHz SSB, lower sideband, located at 104 kHz in a government furnished FDM demultiplexer unit

Low distortion automatic phase control circuit

A voltage controlled phase shifter is rendered substantially harmonic distortion free over a large dynamic input range by employing two oppositely poled, equally biased varactor diodes as the voltage controlled elements which adjust the phase shift. Control voltages which affect the bias of both diodes equally are used to adjust the phase shift without increasing distortion. A feedback stabilized phase shifter is rendered substantially frequency independent by employing a phase detector to control the phase shift of the voltage controlled phase shifter

Low distortion automatic phase control circuit

Circuit for generation and demodulation of quadrature double side band signals in frequency division multiplexing system is described. Circuit is designed to produce low distortion automatic phase control. Illustration of circuit and components is included

Two-component plasma in a gravitational field

In this paper we study a model for the sedimentation equilibrium of a charged colloidal suspension: the two-dimensional two-component plasma in a gravitational field which is exactly solvable at a special value of the reduced inverse temperature Gamma=2. The density profiles are computed. The heavy particles accumulate at the bottom of the cointainer. If the container is high enough, an excess of light counterions form a cloud floating at some altitude.Comment: 17 pages, 3 Encapsulated Postscript figures, LaTeX with the graphicx packag

Adaptive independent Metropolis--Hastings

We propose an adaptive independent Metropolis--Hastings algorithm with the ability to learn from all previous proposals in the chain except the current location. It is an extension of the independent Metropolis--Hastings algorithm. Convergence is proved provided a strong Doeblin condition is satisfied, which essentially requires that all the proposal functions have uniformly heavier tails than the stationary distribution. The proof also holds if proposals depending on the current state are used intermittently, provided the information from these iterations is not used for adaption. The algorithm gives samples from the exact distribution within a finite number of iterations with probability arbitrarily close to 1. The algorithm is particularly useful when a large number of samples from the same distribution is necessary, like in Bayesian estimation, and in CPU intensive applications like, for example, in inverse problems and optimization.Comment: Published in at http://dx.doi.org/10.1214/08-AAP545 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Subsidies and distorted markets: Do telecom subsidies affect competition?

There is general concern that producer subsidies distort competition. We examine a telecommunications subsidy system that transfers money from low cost regions to high cost regions of the U.S. Even though the system is designed to be competitively neutral, we find evidence that the system, combined with carrier of last resort policies, promotes cream skimming by entrants in low cost areas and deters entry in high cost areas, where incumbents are more likely than entrants to receive subsidies. We are unable to rule out the possibility that state regulatory policies favor incumbents in states that are net beneficiaries of the subsidy system.subsidies, Universal Service Fund, telecommunications, regulation