MH-60R - Radar/IFF System Flashcards
(28 cards)
Describe the function of the receiver/transmitter
The receiver/transmitter generates the transmission pulse for the antenna and converts the received pulse from the antenna into a usable form for the RDP to process. The receiver/transmitter hardware generates the radar waveforms and provides variable transmit output power level. The R/T also provides super-heterodyne and stretch receiver functions and analog pulse compression in selected modes.
What are the components of the radar/IFF system?
• Radar receiver/transmitter (R/T);
• Antenna/pedestal (antenna array and IFF interrogator R/T);
• Radar data processor (RDP);
• Radome;
• IFF Mode 4 crypto;
• Waveguide assembly;
• Waveguide dehydrator.
Describe the function of the antenna/pedestal
The antenna/pedestal (A/P) provides for controllable antenna position and azimuth drive for the radar and provides the radar and IFF interrogation signals to the planar array for transmission. The A/P also provides for interrogator and receiver side lobe suppression for the IFF interrogator R/T.
Describe the A/P subsystem
The A/P subsystem consists of the azimuth drive assembly, A/P controller, a radome containing the IFF array attached to the X-band antenna face and an IFF receiver/transmitter assembly. The A/P hardware communicates with RDP for control information and status reporting. The azimuth servo controller drives the antenna at mode-dependent speeds of 12 or 108 rpm, or up to 150 rpm for ARPDD modes.
Describe the Radar Data Processor
The RDP processes the raw radar and IFF interrogator data to form tracks which are presented to the operator on the mission display. The RDP receives digitized antenna azimuth and IFF replies from the A/P, radar video from the R/T, helicopter position from the EGI, and operator mode control command via the mission computer. The RDP provides digital pulse compression in selected modes, radar control, video processing, data communications, tracking and image processing. It also provides IFF interrogation control, IFF code validation and contact reply correlation.
What do the microprocessors do for the RDP?
Microprocessors operate on these inputs to perform Track While Scan (TWS) automatic detection and tracking, IFF/track associations, and digital range/bearing video generation and distribution functions. In addition to the radar and IFF contact replies and associated track data reported to the mission computer, the RDP mixes digitized IFF contact data into the planned position indicator (PPI) video that is sent to the ship via data link. The AN/APS-53(V)1 radar data processor provides ARPDD enhanced processing (AEP) and improved discriminator subsystem (DS). The DS processors perform signal and data processing on the raw contact data in order to provide track merging and track history. The DS also compiles received contact amplitude in a form that can be presented to the operator with unique signatures.
Describe the radome
The radome provides environmental protection for the antenna/pedestal assembly and is relatively transparent to RF energy.
Describe the crypto module
The KIV-6 provides the encryption/decryption functions required for secure IFF Mode 4 operations. It is loaded during pre ight with current day/next day (Mode 4A/4B) keylists and is zeroized after ight. The KIV-6 interfaces with the IFF processor in the RDP.
Describe the Waveguide Assembly
The waveguide assembly transmits the voltage standing wave ratio from the R/T to the A/P and transmits X-band radiation.
Describe the Waveguide dehydrator
The waveguide dehydrator is a passive, desiccant-filled cylinder mounted beneath the mission computer in the SO console avionics rack. The waveguide dehydrator connects to the radar waveguide for the purpose of moisture removal to prevent waveguide arcing.
How does the RDP interact with the MC?
The RDP interfaces with the mission computer (MC) via the 1553B data bus for classi ed data loading, command, control, data, and status functions. The radar operates as a remote terminal on the data bus.
The radar interfaces to the MC via a 32-bit wide digital video interface (DVI). Through the mission computer’s composite color video output, the radar sends processed radar video and digital track data to the MC for formatted display to the operators.
For the APS-153(V)1 radar, a 100baseT Ethernet interface to the mission computer accommodates radar track reports, signatures, and initial program load of the radar and discriminator. In addition, two discrete interfaces, reset and ARPDD present, aid the MC in detecting an APS-153(V)1 RDP versus an APS-147 RDP during initialization.
Describe the function of the blanker
The radar R/T provides a blanking signal to the blanker for transmission to the IFF transponder, ESM, and TACAN when the radar interrogator is transmitting. The radar accepts a blanking signal from the blanker originating from the TACAN and IFF transponder’s reply to interrogations.
With data link, what modes of radar can the ship control?
Legacy: SRCH LONG, SRCH CSTL, and either PERI LONG or PERI ARPDD, if available. The ship is able to monitor data from SRCH SHORT, PERI SHORT and ISAR, but cannot control these modes nor can it command the radar into these modes.
SAU7K: ships that have implemented radar control can control all modes; however, if PERI ARPDD is available, the ship cannot command PERI LONG and PERI SHORT.
How does the WOW switch interact with the radar?
The radar directs the RF energy to a dummy load in response to a weight-on-wheels (WOW) signal. WOW input is also used in the logic for the Refuel Hold function in the IFF Mode 4 cryptographic module. Additionally, AOP uses the WOW message from the mission computer to disable the +RAD ON/OFF function to provide a backup means of preventing radiating on deck.
How does data zero work with the radar?
The APS-147 radar zeroizes all classi ed data in the radar in response to activation of the DATA ZERO switch on the CMP. DATA ZERO in the APS-153(V)1 zeroizes all classi ed data in the radar, but will not clear the discriminator and ISAR algorithms. Mission power must be cycled to clear the discriminator and ISAR algorithms.
How does the radar interface with the navigation system?
The radar interfaces directly with the navigation subsystem via the 1553 data bus to minimize system delays in helicopter attitude, heading, position, and velocity data. This maintains system accuracy in the tracking, targeting, and imaging modes. The radar acts as a bus controller on the navigation interface to obtain data from the EGIs.
What are the radar modes of operation?
• Standby (STBY)
• Short Range Search (SRCH SHORT);
• Long Range Search (SRCH LONG);
• Coastal Search (SRCH CSTL);
• Short Range Periscope Detect (PERI SHORT);
• Long Range Periscope Detect (PERI LONG);
• Automatic Radar Periscope Detection and Discrimination (PERI ARPDD)(AN/APS-153(V)1 only);
• Inverse Synthetic Aperture Radar (ISAR);
SRCH SHORT data
Scan rate: 108
Instrumented range:
Radar: 100 yds - 16 NM IFF: 100 yds - 75 NM
Mission display zoom levels:
0.25 - 256 NM
Brief description:
Optimized to detect both large and small contacts
at short ranges. Used for low-visibility approaches and situations requiring display of closely spaced contacts.
SRCH LONG
Scan rate: 12
Instrumented range:
Radar: 0.25 - 160 NM IFF: 100 yds - 160 NM
Mission display zoom levels:
4-256 NM
Brief description:
Standard long-range surveillance detection mode of radar.
PERI LONG
Scan rate: 108
Instrumented range:
Radar: 2-32 NM IFF: 100 yds -75 NM
Mission display zoom levels:
2-256 NM
Brief description:
Optimized to detect small targets such as periscopes, submarine snorkels, mines, or lifeboats in the presence of sea clutter.
PERI SHORT
Scan rate: 108
Instrumented range:
Radar: 100 yds - 16 NM IFF: 100 yds -75 NM
Mission display zoom levels:
0.25-256 NM
Brief description:
Optimized to detect small contacts such as periscopes at short ranges.
PERI ARPDD
Scan rate: 154
Instrumented range:
Radar: 100 yards - 30 NM IFF: 100 yards - 45 NM
Mission display zoom levels:
0.25 - 256 NM
Brief description:
Provides for range pro le of a target. High range resolution tracks closely separated tracks. Detects probable periscopes and presents to the operator as symbols on the mission display.
ISAR
Scan rate: 0
Instrumented range:
5 - 160 NM
Mission display zoom levels:
N/A
Brief description:
Provides for two-dimensional image of designated surface contact for purpose of identifying ship class.
SRCH CSTL
Scan rate: 12
Instrumented range:
Radar: 0.25 - 160 NM IFF: 100 yds - 160 NM
Mission display zoom levels:
4-256 NM
Brief description:
Optimized to display coastline detail.
