The spectral density of the scattering matrix for high energies

We determine the density of eigenvalues of the scattering matrix of the Schrodinger operator with a short range potential in the high energy asymptotic regime. We give an explicit formula for this density in terms of the X-ray transform of the potential.Comment: 11 pages, Latex 2

High Power GaAs MMIC Chipsets for 18 to 32 GHz Frequency Band Applications

Recent commercial wireless applications such as Point to Point radio links, LMDS (Local Multipoint istribution Service), LMCS (Local multi-point Communications Service) and Commercial K-Band Satellite based services have spurred significant activity in development of mmWave power amplifiers. These applications lie in the frequency range of 18 to 42GHz with possible future extensions to 60GHz. These systems employ digital modulation schemes for which highly linear mmWave power amplifiers are essential. This paper presents an overview of some chipsets consisting of High Power amplifiers covering the frequency range of 18 to 32GHz. Preferred solutions to a low cost subsystem vary from one subsystem manufacturer to another as it involves assembly and test capabilities in addition to component costs. The overall direction appears to be toward multi-chip moduleassemblies. Here, both chip and packaged level component options are considered