CTJC contracts or subcontracts to Federal, State and local government agencies, as well as, to industry groups, providing communications engineering services in the areas of communications systems and facilities design, test and evaluation, electromagnetic environment characterization, and special test design and implementation. CTJC has provided expertise in numerous communications systems design, test and evaluation projects, examples of which include: the design, implementation and demonstration of a low frequency groundwave emergency alerting network for the US Air Force; test and verification of fixed and mobile meteor burst communications links; and test and evaluation of subsurface and near surface dipole and crossed dipole antennas. Utilizing our strong measurements background, the corporation has successfully completed several projects for the military and private contractors to characterize the ambient electromagnetic environment in order to predict the performance of sensitive communications receive equipment or to evaluate the potential for disruption to sensitive electronics equipment. Our engineers have designed systems and performed electromagnetic environment measurements on military ships, on aircraft, and within computer vaults. Several years ago, our engineers conducted a continuous spectrum measurement program over several days and nights in order to characterize the electromagnetic environment on a number of building rooftops in Washington DC when the Federal Communications Commission was evaluating candidate locations for the Agency and their ability to maintain sensitive monitoring functions. Our engineering staff has extensive experience in special test design and implementation and the corporation has designed and performed numerous special test projects for various industry groups. Most recently CTJC engineers designed and performed tests under contract to the National Cable Telecommunications Association to evaluate the susceptibility of modern television receivers to interference from "White Space" communications devices in the VHF and UHF spectrum. As part of this test program, our engineers also performed tests to determine the potential for "White Space" device interference to cable "headend" reception of off-air television broadcast signals. Similarly, under contract to the National Association of Broadcasters, CTJC engineers designed and implemented tests to assess the susceptibility of modern FM receivers to co-channel, and adjacent channel interference. The results of the test program were used to assess the impact of the proposed introduction of a Low Power FM Service within the FM band. CTJC engineers have the experience and knowledge to help you solve your next communication system challenge.