The spatially uncorrelated feature of the transmission signals is produced using Walsh-Hadamard code sets; then multipath delayed waves are produced for each signal, and finally a different Doppler shift is added for each probe antenna. Rayleigh fading is thus obtained by spatial synthesis of the signals emitted from the probe antennas in a configuration for amplitude and delay control for each path in the connection matrix that is far simpler than conventional path-control methods.
where [W.sub.TX] is a TX-side connection matrix with L x M dimensions consisting of a set of Walsh-Hadamard code vectors, with the matrix producing independent Rayleigh fluctuations against M input signals, and [A.sub.RX] is the N x L channel matrix connecting the probe antenna array with the reception antenna array.
Delay generator: A function that imparts a delay time and an amplitude level to each probe antenna when each incoming wave has different delay time and amplitude level.
Doppler shifter: A function that imparts vehicle speed (Doppler frequency) information to each probe antenna.
It was shown that the basic field transformation equations are cumbersome to evaluate, and the consideration of a measurement probe antenna makes the problem even more involved.
([parallel]) For this, it is assumed that mutual interactions involving the probe antenna are negligible.
In (3), [E.sup.tx]([omega], [r.sub.s]) and [E.sup.rx]([omega], [r.sub.s]) denote the fields from the transmitting metamaterial aperture panel and the receiving probe antenna projected to the point [r.sub.s], respectively.
(a) Overall system consisting of a transmitting metamaterial panel (excited using six coaxial probe feeds and L = 50 cm) and a low-gain receiving probe antenna placed at the panel center; (b) metamaterial aperture panel.
However, traditional antenna measurement techniques have limitations in antenna on a probe station, for which the conventional methods are based on spherical measurement requiring complex mechanical arms for the probe antenna
movements around the AUT [9-11].
To make antenna pattern measurements, the probe antenna
is supported fixed in space, while the AUT is mounted on the azimuth positioner and stepped in angle in the azimuth plane.
This reduction results from swinging the probe antenna
on an arc that approximates the perfect focal arc defined by r = [R.sub.0] cos [theta].
Subsequently, E-Systems installed inertial navigation systems and HF probe antennas
on the aircraft and has already undertaken a series of "life extension" upgrades on the subsystems within the core sensor suite and its related ground stations.