Modulation of l/f Noise by Mass
( 4-16-1985 )
A. Shielded C-mos Circuit #15 (1600 uF)
1. Local “Effects”a. Heartbeat
This is a strong modulation which does not appear to be diminished from 50 ft away! Modulation “beat” tracks pulse rate exactly!
b. Pendulum swing (8 oz)
This is a “swishing” sound which follows the pendulum swing exactly. The heart beat sounds are interposed and hard to detect until the pendulum swing diminishes to lower excursions.
c. Spinning offset weight on motor
This is a small mass moving in about a one inch (1”) radius. It is discernable because of its higher spin rate (frequency).2. RemarksB. Potential uses of this effect.a. The heartbeat, of course, cannot be removed from these tests.
b. The pendulum swing, however, and the motor spin, can be stopped, removing their effects in l/f modulation.
c. There are many outside modulations, terrestrial or space, which also are not controllable.(1) Gravitational Communicationsa. The l/f modulation can be useful in some sort of coherent pulse modulation communication system.
b. With l/f noise cancelled in a large measure, it may be possible to have some sort of analog signal communication system.(2) Intrusion Alarmsa. Since body movements and the heartbeat results in strong modulation of l/f noise, this is an intrusion alarm system which is passive and cannot be circumvented! The detection is independent of local masses such as building and machinery. The only development needed here is the extraction of the modulation in useful levels needed to trigger alarm circuitry.(3) Military Usesa. Possibility of submarine detection by ships and vice versa.
b. Torpedo detection due to signature.
c. Aircraft detection due to signature.