Abstract: A method and system for flexible radio communications using a wideband radio includes a wideband radio and multiple separable radio definition modules, wherein the wideband radio is configured to operate over a large portion of the radio-frequency (RF) spectrum and each of the radio definition modules are configured to operate in a specific frequency band. The separability of the radio definition modules maintains the capability of the wideband radio to operate over the large portion of the RF spectrum, as well as enabling its robust and reliable operation in a specific frequency band associated with the attached radio definition module.

Abstract: A method and system for flexible radio communications using a wideband radio includes a wideband radio and multiple separable radio definition modules, wherein the wideband radio is configured to operate over a large portion of the radio-frequency (RF) spectrum and each of the radio definition modules are configured to operate in a specific frequency band. The separability of the radio definition modules maintains the capability of the wideband radio to operate over the large portion of the RF spectrum, as well as enabling its robust and reliable operation in a specific frequency band associated with the attached radio definition module.

Abstract: An enclosed ion source for generating substantially monoenergetic ions from a gaseous sample comprises a chamber into which the gaseous sample is introduced and which is substantially enclosed by a source block having two electron entrance apertures formed in it and by a source plate having one ion extraction aperture formed in it. Two filaments are disposed outside the chamber and adjacent the electron entrance apertures. The electron impact ion source is characterized by the provision of an electrically conductive shield which is disposed within the chamber and which defines an equipotential region. The electrons, generated from a heated filament, pass into the chamber through one of the electron entrance apertures. The shield allows the passage of molecules of the gaseous sample and the electrons into the equipotential region, so that electron impact ionization of at least some of the sample occurs in the equipotential region.