Acoustic Noise Suppression in Airborne Communications.
Abstract
One of the major recommendations of ECOM Report 4140 (AD-767 222) was the improvement or replacement of the M-87 microphone with one that had improved noise cancelling capabilities and a flatter frequency response. This area of concern is covered extensively. A program has been established to further evaluate militarized, improved-microphone candidates for possible incorporation into the Army system in FY-77. Another recommendation of ECOM Report 4140 was the improvement of the Heli-Notch filter (presently on all CH-47 aircraft) with an extended frequency response and the capability of eliminating all pure tone components not cancelled by the microphone. One such filter was investigated and was found to be somewhat successful in achieving this goal. An AD phase of the whine filter development is expected to begin in FY-76.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1975
- Accession Number
- ADA013365
Entities
People
- Mitchell S. Mayer
Organizations
- United States Army Communications-Electronics Command