Publications

A Transportable Measurement Facility (TMF) incorporating antenna, r-f, and reply processing elements of a Discrete Address Beacon System (DABS) sensor has been sited at, and in the vicinity of, several FAA terminal ASR's throughout the United States. Data collected at these sites have been thoroughly analyzed to verify the design of the DABS sensor and to establish the need for design refinements. This report presents the results that pertain to DABS and ATCRBS Mode range and azimuth accuracy and to the total ATCRBS Mode reply processing performance, It is shown that both range and azimuth accuracies for the DABS sensor are a factor of four to five better than those provided by existing ARTS (BI-4) interrogators, and that the average blip/scan ratio is 98% or better, dropping only a few percentage points in crossing track situations.

This report discusses the transition from the ATCRBS-based surveillance function with voice radio only to a DABS-based surveillance function with integral digital communication capability to support IPC and automation. Recommendations are directed toward alleviation of certain problems already evident and toward preparation for the deployment of DABS beginning in the late 1970s. An evaluation of the present ATCRBS system indicates basic adequacy in the present environment for the current mode of operation of the ATC system. The introduction of automation into the ATC system requires capability in the areas of data link and enhances surveillance reliability for automatic tracking that the DABS system will provide. On this basis it is concluded that the ATCRBS system does not need major modifications to continue its role into the DABS period at locations where the environment and operation will be similar to that presently encountered. A number of recommendations are made regarding radar where new technology can provide significantly enhanced performance at little added cost. The introduction of a digital data link provides many opportunities and challenges. Most of them associated with tactical message handling are being addressed within the DABS program but attention is called to a related set of issues for messages originating from or destined for other than ARTS or NAS (e.g., FSS).