TM-9-1290-365-24&P Technical and Parts Manual for Paladin Muzzle Velocity System M93 Upgraded Download
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ARMY TM 9-1290-365-24&P e. High altitude during air transport f. Rain and wind g. Sand and dust h. Solar radiation (direct sunlight) i. Salt fog j. Environments leading to growth of fungus 1.15 PRINCIPLES OF OPERATION. The M93 MVS Transceiver is a compact Doppler transmitter-receiver that generates a Doppler signal related to the velocity of projectiles fired from the gun on which the transceiver is mounted. The gun firing is detected by an automatic triggering device which starts the measuring process (transmits RF-energy). The transceiver transmits RF energy only when the system is in measure mode. The system transmits a low-power signal in the X band range. The echo frequency returned from the projectile is shifted in frequency relative to projectile velocity. This frequency undergoes mixing with the transmitted frequency in order to achieve a Doppler frequency: F d = F t - F r = 2F t V C Where: F r - frequency received by antenna F t - frequency transmitted by antenna C - speed of light V - projectile velocity relative to gun F d - Doppler frequency Projectile velocities between l50-1500 m/sec will generate a Doppler frequency between 10-100 kHz. This frequency is sampled and processed in order to derive the projectile muzzle velocity. Using the Doppler effect and fast fourier transform algorithm (FFTA), the projectile instantaneous velocity is measured at up to 64 predefined in-flight intervals. This data is sorted by statistical methods to calculate the best fit regression curve and used to extrapolate the projectile velocity upon exiting the gun tube (Muzzle Velocity - MV). 1.16 MUZZLE VELOCITY MEASUREMENT AND CALCULATION. The MVP starts the Doppler sampling process when triggered by a signal received from the transceiver. This instant is referred as t = 0. The Doppler signal is then processed to obtain the projectile's velocity at several predefined instances. The requested MV is obviously V(t = 0). This value can be calculated by finding the best-fit linear regression curve of the form: V(t) = at + b Where: t - Time in seconds V(t) - Instantaneous velocity a,b - Linear regression constants. 1-10