IFF Reply Coding
Abstract
In a transponder type of IFF system, cryptographically coded, deliberate garbling of the code by an enemy to appear friendly must not be permitted. To prevent this, frequency-coding is more satisfactory than pulse-coding, but the latter may be suitable for the auxiliary function of aircraft control. The probability of deception by guessing the correct code is computed for several system designs, and it is shown that a relatively small number of reply codes is ample to make this probability low if appropriate integration of replies is required before deciding that the indication is friendly.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 31, 1949
- Accession Number
- AD1211605
Entities
People
- C. E. Cleeton
Organizations
- United States Naval Research Laboratory