Can the Spectrem Transmitter and Processing Work on a Small Helicopter Platform?

The Spectrem waveform and processing has many advantages. The possibility of implementing this on a central-loop helicopter platform was investigated. Data was acquired in early 2008 with ground and flight tests. The amplitude of the anomalies produced by the Step Response processing are modulated by the amount of primary field present at the receiver. The smaller the primary field (larger “Bucking Factor”), the larger the anomaly amplitudes, however this makes the system more sensitive to geometric changes. The ground and flight tests suggest that the Spectrem waveform and processing is not suitable for a central loop helicopter system due to it’s sensitivity to geometric changes.