MISTRAM
A "classic" ranging system used since the 1960s uses radar to time a radio signal's travel to a target (in this case, the rocket) and back.
The accuracy of this technique is limited by the need to create a sharp "pulse" of radio so that the start of the signal can be accurately defined.
The basic system used a ground station located down range from the launch site (at Valkaria, Florida and Eleuthera Island, Bahamas) and a transponder on the vehicle.
By slowly changing the frequency of the carrier broadcast from the station and comparing this with the phase of the signal being returned, ground control could measure the distance to the vehicle very accurately.
To meet more stringent ballistic missile test requirements, several systems were designed, procured and added to the US Air Force Eastern Range's instrumentation in the 1950s and 1960s.
Assume also that the phase can be measured with an accuracy of 1 deg, i.e. means that the range can be determined with a precision of (600000*1*Pi)/(2*8000*180)=0.33 km.
[1] MISTRAM was a multistatic long baseline radar interferometer developed for precision measurements of missile trajectories at the US Air Force Eastern Test Range.
Multistatic radar systems have a higher complexity with multiple transmitter and receiver subsystems employed in a coordinated manner at more than two sites.
All of the geographically dispersed units contribute to the collective target acquisition, detection, position finding and resolution, with simultaneous reception at the receiver sites.
A two-way transmission path on each baseline was used to cancel out uncertainties due to variance in ground geometry and temperature.
with design performance as follows: The Transponder receives the two phase-coherent X-band cw signals transmitted from the ground equipment.
This high speed 36-bit minicomputer was developed by the GE Heavy Military Electronics Department (HMED) in Syracuse, New York.
The M236 was designed for real-time processing in a radar-based missile flight measurement system and lacked some general purpose features, such as overlapped instruction processing, the floating point operations needed for Fortran, and operating system support features, such as base and bounds registers.
[6] The debate in favor or against subsequent development of an M236-derived general purpose computer took more than one year and concluded finally with the victory of the M2360 project proponents in February 1963.
During the Minuteman II flight test program, significant improvements were made in the post-flight evaluation of the IMU accuracy.
Continued improvement of the UDOP and MISTRAM tracking systems and refinement of the evaluation techniques during the Minuteman III flight test program made it possible to gain considerable insight into NS-20A1 IMU error sources.
A statistical technique was developed that performs a variance-covariance propagation to obtain accuracy estimates based on random and unmodeled errors.
MISTRAM was designed and developed by the Heavy Military Electronics Division, Defense Systems Department of the General Electric Company, Syracuse, New York, under the sponsorship of the U.S. Air Force Missile Test Center, Patrick Air Force Base, Florida (Contract AF08 (6060) 4891).
