User's Manual Part 4

T ECHNICAL D OCUMENTATION P ROTECTING P EOPLE AND A SSETS
®
D
ATE
:
27
M
ARCH
2017
|
V
ERSION
:
1.8
82
R
ANGER
®
-
X5
R
ADAR
S
YSTEM
(M
OBILE
)
F
UNCTIONAL
O
VERVIEW AND
T
HEORY OF
O
PERATION
EEC
®
|
C
OMPANY
P
ROPRIETARY
the received IF and outputs I and Q serial data through fiber-optic cable to the Fiber-Optic Rotary
Joint. The data is coupled through the Fiber-Optic Rotary Joint and sent to the IQ2-DSP in the
Control Cabinet.
4.4.2. IQ2-DSP
The IQ2-DSP digitally processes the “I and Q” data stream from the IQ2-IFD, already broken into
range-gate intervals, with floating-point algorithms to provide all required moments.
4.5. Antenna Control
The user utilized the EDGE software or the LCI software on the RCU to send commands or EDGE
Software to provide Antenna control. The positioning commands are provided through an Ethernet
connection to each axis Aquarian Servo Controller Module, which develops the drive signal for the
Servo Amplifier and drive motors to move the Antenna.
The RCU breaks the high level command down into intermediate motion type, some are simple
(Point, PPI) some are more complex and require the RCU to execute a state machine to control the
desired motion (Sector, RHI). Once the RCU converts the high level command into a intermediate
level it is sent to the servo control for further processing.
The Aquarian takes an intermediate level command from the RCU to generate a motion profile in
real time. This process is known as trajectory generation. For the desired motions to be successful,
the trajectory generator outputs a command for each sample period telling the servo system the
position of the motor. The Aquarian samples the encoder for each position axis. The actual position
combined with the trajectory information creates a closed loop drive signal known as “error.” The
servo amplifier uses the “error” signal to actual the DC brushless motor.
The moving mass of the antenna system can be a hazard to personnel when performing maintenance on
the radar system. The Aquarian controller has a “safe input” that requires a ground signal to be applied in
order for the antenna to operate in a normal fashion.
4.5.1. Angle Acquisition
The Aquarian samples the incremental encoder via a dedicated high-speed quadrature Integrated
Circuit decoder. The sampled encoder positions are converted to angular data in degrees. This
resolved position uses a feedback in the closed loop control and is sent to the RCU. The RCU
receives angle data via Ethernet from the Aquarian. This data is corrected for true north by an offset
stored in the RCU. The data is transferred to the signal processor via high-speed RS422 serial link.
4.5.2. Homing Sequence
A homing sequence is required for each axis in order to resolve the incremental units of the axis