General Information; Functional Overview - DBM ACE9600 Operating Manual

dBm
ACE600
Operations Manual
Advanced Channel Emulator
Ge n e ra l In fo rm a tio n
Fu n c tio n a l Ove rvie w
ACE9600 reproduces link effects that occur as signals propagate
though the atmosphere and space. These link effects include propagation
delay, carrier Doppler shift, chip rate shift, path loss, ionospheric
scintillation, mutipath fading , and troposcatter effects. The ACE9600
reproduces those effects by generating time varying delay, attenuation,
carrier Doppler shift, phase shift, AWGN, and 12 path multipath fading.
The ACE9600 also has the capability to emulate distortions caused by
hardware. Those distortions include signal compression, intermodulation,
and AM/PM that result from power amplifier non-linearities, additive phase
noise that results from non-pure local oscillators and clocks, group delay
slope and amplitude slope that result from band limiting filters and
multiplexers, and spurious signals that may be generated in internal signal
sources or from external interfering sources.
The ACE9600 allows the user to set these parameters to fixed values. This
is the Static mode of operation. In Dynamic mode operation, delay,
attenuation, Doppler shift, phase offset, AWGN, and multipath fading can
be varied in real time to emulate changes in the relative position of
communication platforms (the remaining parameters remain at a fixed
setting during dynamic operation). The values of the parameters are
controlled by data files that can be generated by the user or via SATGEN,
an application that creates the files based on ephemeris satellite data, mobile
and fixed ground terminals, ground vehicles, and aircraft. Carrier Doppler,
attenuation, and additive white Gaussian noise can be varied at time
intervals ranging from 1 msec to 1000 msec. RF frequency and multipath
fading parameters can be executed at time intervals between 10 msec and 1
second. The number of points per file is limited only by the removable on-
board SD card memory size. The RF output signal remains phase
continuous during all dynamic updates. The time varying delay causes chip
rate variations.
The RF interface of the ACE9600 can be configured as either a fixed IF
frequency, or tunable over the L-band range of 800 – 2600 MHz. When L-
band is included, the RF frequency can be set to a fixed value, or when
dynamic mode is active, the RF frequency can also be varied in real time.
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