Bearing Study Program.
Abstract
A study was conducted to assess the feasibility and define the system accuracy and equipment required to add a bearing measurement subsystem to the SECANT Collision Avoidance System (CAS). The results indicate the feasibility of achieving the accuracy required to serve useful functions. Equipment configurations required for Proximity Warning Indicator and CAS applications were evolved and are presented in detail in this study. The approach utilizes a ring array antenna consisting of vertical monopoles interconnected by stripline. It has a high accuracy outer ring of 16 monopoles, an inner ring of 4 monopoles for resolving ambiguities, and a central reference monopole. The array receives the signals transmitted by any of the equipment types in the SECANT family, and the relative bearing is determined by measuring the phase difference between the signals in the reference monopole and in the rings. Random errors are minimized by integration of the high pulse rate, frequency hopped signals. Predicted overall error is 1 degree, one sigma with a bias component of 0.8 degree and a random component of 0.5 degree. An antenna array was constructed and tests in an anechoic chamber confirmed the validity of the design approach.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1974
- Accession Number
- ADA049767
Entities
People
- Bernard Case
- Ernest Jellinek
- M. Levinsen
- O. M. Woodward
- Walter Kram