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Design and production data of BVA quartz crystal resonators and oscillators have been presented in the past at the Frequency Control Symposium. [1,2,3,4]. The BVA 5 MHz crystal equipped frequency sources exhibit a new blend of remarkable performances such as 10-11 daily stability ,5x10-13 short term stability (1 to 30 s time intervals) and close to the carrier low phase noise (1 Hz : -120 dBc, 10 Hz : -140 dBc), whereby retaining the customary crystal oscillator benefits of small volume, high reliability and low price, as opposed to more sophisticated frequency generators which would be required to achieve comparable performances. Examples illustrating the impact of the Oscilloquartz BVA OCXO in different frequency generating systems will be presented : -in cesium frequency standards - in a hydrogen frequency standard -in a precision distribution sub-system for satellite ground stations - in high hierarchy exchanges of digital networks, synchronized by the master-slave method., Presented at the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (16th), held in Greenbelt, Maryland on 27-29 November 1984. Published in Proceedings of the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (16th), p167-190, 27-29 November 1984.

This report contains the results of the continuation of Marine Air Traffic Control and Landing System (MATCALS) investigations. The report is organized into three main sections, namely Part Two, Part Three, and Part Four. Part Two presents a method of estimating the centroid location of a target utilizing a scan return amplitude versus angle information. Part Three contains the results of an investigation into replacing the alpha-beta filter in the MATCAL digital controller with an observer, in order to reduce the effects of radar noise. Part Four presents the results of an investigation into replacing the same alpha-beta filter with a tri-state adaptive filter, in order to reduce the effects of radar noise., See also Volume 2, AD-A110 863, and AD-A107 384.

The report is organized into three main sections, namely Part Two, Part Three, and Part Four. Part Two contains the results of an investigation into replacing the alpha-beta filter in the MATCALS digital controller with an observer, in order to reduce the effects of radar noise. Part Three presents a centroid algorithm based up return amplitude-versus-angle signature. Part Four presents an investigation of adaptive filtering algorithms for the MATCALS system., Prepared in cooperation with Georgia Inst. of Tech., Atlanta, GA. Engineering Experiment Station.

This final report describes components of a real-time Radar Operating System (RADACS) for an SEL86 computer controlled cross-bow phased array radar set. The report is composed of 5 separate parts, each describing a portion of the contract performance. (Author)

The BVA consists of an electrodeless resonator which is decoupled from its mounting structure by four bridges. These bridges have a width of only .4 mm to get the mounting stresses away from the active centerpart as much as possible. The electrodes are plated on two more pieces, called condensors, which are made also of AT Quartz blanks with the same cutangle as the resonator blank. Since the BVA is designed an an oven quartz this is the only possibility to avoid stresses due to thermal expansion. The three parts, we call it sandwich, are rigidly hold together with clips made from stainless steel. To protect the fragile bridges against shocks the whole sandwich is mounted with springs into a rigid cage consisting of the base plate and a cover plate which are fixed to 4 columns., This article is from the Proceedings of the Annual Symposium on Frequency Control (37th), 1-3 Jun 83, Marriott Hotel, Philadelphia, Pennsylvania, AD-A136 673, p492-500.

The report discusses the SEL86 radar operating system, a collection of programs that controls the radar, collects data and communicates with the operator. There are three major levels to this system. The inner most level is the NUCLEUS whose main purpose is to provide process synchronizing and basic resource allocation. The next level is the SUPERVISOR which provides an interface to the NUCLEUS and input/output and other services to the control programs. The outer level is made up of the RADAR CONTROL PROGRAMS which performs the actual radar control functions. The report contains two articles: SEL 86 Radar Operating System, and Frequency Agility to Reduce Multipath Pointing Errors.

A design for a sixty-four way planar power divider in stripline is developed. The power divider is designed to meet specific requirements: frequency range of 5.25 to 5.75 GHz, VSWR less than 1.3:1, output amplitude difference between channels of plus or minus 0.5 dB, output phase difference of plus or minus 6 degrees, isolation between sum and difference ports of 40 dB minimum with the outputs terminated in matched loads and 35 dB minimum with the outputs terminated in shorts, power handling capabilities of 50w average and 5 Kw peaks, and output impedances of 50 ohms at each termination. (Author)