FCS

Question 1

What is the purpose of the FCS?

Answer 1

To provide HMCS CHARLOTTETOWN with a means of tracking targets and generating the fire control solution for the Guided Vertical Launch System and the 57 mm Gun engagements

Question 2

What is the Director Antenna?

Answer 2

The antenna is located on the director. The director for system A is located on the bridge top, while the director for system B is located on the hangar top. The antenna is a Gregorian type with a polarization-twisting main reflector, which means it has a concave secondary reflector. It uses an X-Band for the CWI and Ku-Band for tracking. It has 3 feed horns: one for the tracking radar, which is located close to the main reflector, and two for the CWI. It also has a monopulse comparator.

Question 3

What is the RU Cabinet?

Answer 3

The radar unit cabinet contains the transmitter, receiver, travelling wave tube, and a card rack. Inside the RU cabinet, a stabilized local oscillator (STALO) uses two phase-locked LOs to generate an IF. One LO is used to transmit, while the other one is tuned to the next frequency to be used allowing for very rapid frequency switching. The RF energy is then amplified by the TWT and fed to the monopulse unit, which then sends it to the feedhorn. Received RF energy is collected by the monopulse unit and three signals are generated here: sum, elevation error, and azimuth error. The error signals are sent to the DCU, and the sum channel is sent to the downconverter. The IF from the downconverter enters the receiver, which extracts the I and Q data then is sent to the DCU for processing.

Question 4

What is the sensor unit?

Answer 4

The sensor unit, which is mounted on the elevation turntable, houses heaters, an IR camera, a laser rangefinder and a TV camera. The SU allows for optronic tracking. The TV camera tracks targets based solely on contrast.

Question 5

What is the servo unit?

Answer 5

This consists of two turntables (elevation and train) and hydraulic motors (powered by oil from the HPU) to slew the director. Each hydraulic motor is controlled by a servo-operated valve. The azimuth turntable contains a slipping assembly, allowing for electrical and hydraulic connections to be maintained while the antenna rotates. When the Director is set to deck-set mode, a locking pin is inserted into each turntable using a spring.

Question 6

What is the support unit?

Answer 6

This consists of shock absorbers. It provides the structural support for the director.

Question 7

What is the Dry Air Unit (DAU)?

Answer 7

This unit provides dry, pressurized air to the antenna and waveguides.

Question 8

What is the hydraulic pump unit?

Answer 8

This provides the pressurized oil for the hydraulic motors in the Director. It contains a motor, pumps, and an oil tank. It interfaces with the ship’s chilled water system IOT cool the oil, which is then used to cool the system and the TWT inside the RU.

Question 9

What is the System Interface Unit (SIU)?

Answer 9

The SIU is a node that manages the start and running of the FCS. It runs Resource Manager IOT perform the start-up, node configuration, and monitoring status. It also runs the Navigational Data Distribution System Adapter which receives nav data and distributes it to the other nodes.

Question 10

What is the Launcher Control Unit?

Answer 10

The LCU provides control of the GMVLS and CWI systems. The LCU implements engagement planning, missile assignment, missile engagement, and post-firing evaluation functions. It provides the fire control solution to the GMVLS LCP as well as the illumination frequency

Question 11

What is the Director Control Unit (DCU)?

Answer 11

This node performs radar signal processing, video tracking, and control of the director platform and sensors.It also controls the TV camera and performs video tracking. It receives data from CMS, processes it, calculates angular velocities, and distributes it to other nodes. When the target has been acquired, the DCU sends servo commands to the director based on the error signals generated by the DCU’s radar signal processing/video tracking software.

Question 12

What is the Director Power Unit (DPU)?

Answer 12

This provides an HMI for manual control of the director for testing purposes and converts power for the camera.

Question 13

What is the controller cabinet?

Answer 13

This cabinet contains the control logic assembly (CLA) and the stabilized master oscillator (STAMO).

The CLA performs the overall control of monitoring of the system and the communicating with its FCC.

The STAMO produces the required RF signal. It consists of a reference signal generator, waveform synthesizer, and electronic frequency converter. A STAMO is used because it produces a very stable RF signal. This is important as the ESSM requires accurate Doppler information.

Question 14

What is the Auxillary Cabinet

Answer 14

The auxillary cabinet contains filters, transformers, and power supplies IOT take 440V, 60 Hz, 3-phase power and convert it into four 300VDC outputs IOT supply the amplifiers in the power amplifier cabinet.

Question 15

What is the Power Amplifier Cabinet?

Answer 15

This cabinet contains the amplifiers for the CWI system. There are 96 solid state amplifiers in total which amplify the signal to 200 W for low power mode and 2kW for normal modes.

The power amplifier cabinet also contains a dummy load and waveguide switch.

Question 16

What is the Environmental Support Cabinet?

Answer 16

This cabinet provides cooling for the power amplifiers and pressurized dry air for the waveguides. A liquid-to-liquid heat exchanger uses sea water to cool a secondary coolant (water). This is then circulated through the Power amplifier cabinet.

Question 18

What are the Fire Control Consoles?

Answer 18

Two FC Consoles are located in the aft-port side of the ops room which act as the human-machine-interfaces for the system. Each console is able to interface with either director and consists of a touch input device, a firing switch, console computer and a network connection

Question 19

What are the working modes?

Answer 19

Locked, Standby, Designate, Acquisition, Track

Question 20

What is locked mode?

Answer 20

The director is moved to its parked position and locking pins are inserted

Question 21

What is standby mode?

Answer 21

Locking pins are withdrawn and the director is now able to be set to other modes. The director will periodically perform radar and servo calibrations.

Question 22

What is designate mode?

Answer 22

The director is ordered to point in a direction, either manually or a hooked track

Question 23

What is Acquisition mode?

Answer 23

This mode comes after designate mode and is when the director will begin searching. If a target is detected, the director will immediately stop and slew to the exact position where the detection was made. If it manages to make another detection, it enters track mode. If it is unable to detect it, it returns to its search pattern.

Question 24

What is track mode?

Answer 24

The director begins actively tracking the target. A fire control solution can now be generated in this mode and track data is passed on to CMS.

Question 25

What are the radar modes?

Answer 25

Frequency Agility (FA), Moving Target Indication (MTI), and Pulse Doppler (PD)

Question 26

What is Frequency Agility radar mode?

Answer 26

In FA mode, with each radar pulse, the radar automatically switches between the 128 frequencies it can use.

Question 27

What is MTI mode?

Answer 27

Moving target indication. In this mode, stationary targets are filtered out IOT remove excessive clutter. The radar will send out four pulses and then shift to another frequency IOT still provide some jam resistance.

Question 28

What is the pulse Doppler radar mode?

Answer 28

PD is used in environments with high amounts of clutter/reflections. It uses the Doppler shift to identify the actual target. This means that PD is only available if the target speed is already known. PD sends out 32 pulses before frequency hopping so it is not very jam resistant.

Question 29

What is the functional description for FCS?

Answer 29

CMS is currently operating in semi-automatic mode and the FCS is currently in Standby mode. A small aircraft is detected by the SMART-S. CMS proposes an engagement plan using the 57 mm Gun and FCS A. The AWWO selects “approve” at their MFW. CMS passes track and target information to FC Cabinet A via the Core Switches and the FCS is told to acquire the target. The track data is processed by the DCU and is distributed to the other nodes. FCS A enters Designate mode. The DCU provides servo orders IOT slew the director to the direction of the target. Once slewed, FCS A automatically enters Acquisition mode. The DCU moves the Director in a specific search pattern. Inside the RU Cabinet, the STALO generates a reference signal which is used to tune two LOs, which will create the RF signal. The RF is unconverted, amplified by the TWT, and sent to the monopulse comparator, which transmits it. The RF travels out, hits the sub-reflector and then reflects off the main reflector. It then travels through the atmosphere and reflects off the target. The RF return is received by the monopulse comparator. The two difference channels are used to generate bearing and elevation error signals for the DCU. The sum channel output is sent to a down converter. The DCU processes the signal and determines that there is a target there. The Director is ordered to stop and slew back to where the detection was made. A second detection is made; FCS A now enters track mode. The bearing and elevation error signals are received by the DCU, which slews the director IOT drive the errors to zero. Track data is fed to CMS and distributed throughout the FCS. CMS orders a salvo of five rounds of 3P ammunition. The GCU uses the ballistic tables for 3P, track data from the DCU, and ship’s attitude and MET data from the Nav Suite IOT dynamically calculate the fire control solution. It converts this solution to loading, fusing, and laying orders for the 57 mm. CMS sends the fire command to FCS A. The GCU then sends a firing order to the 57 mm which fires five rounds at the target. The target is assessed killed based on sudden deceleration. The director then slews back and re-enters Standby mode.

Question 30

What are the system interfaces?

Answer 30

- EPG&D: to provide power to the components - Weapons Veto Panel: To make the system electronically safe - CMS: To receive and pass on track information and to display to the consoles through the core switches - 57 mm gun: to receive gun status and give gun orders through the GCU - GMVLS: connected through the LCU to calculate and give launching orders for the ESSMs - CWI: connected through the LCU to provide a rear reference and pencil beam for the ESSMs - Nav Suite: Connected through the SIU to NDDS. Ceros 200 FCS is a critical user meaning it receives two feeds of ship’s attitude data and heading data. - Chilled water: To cool the hydraulic oil for the HPU for the Director - HVAC: To cool the FCER 1 & 2 and the Ops room

Question 31

What are the survivability & redundancy considerations?

Answer 31

- Two independent systems (A&B) - Each system is connected to both core switches - Battleshort - All cabinets are ruggedized and shock mounted

Question 32

What are the safety considerations?

Answer 32

- RADHAZ precautions while at sea and alongside (SEMS S9) - High voltage precautions - High pressure hydraulics in the HPU and at the director.