Aircraft Equipment  - COFDM Downlink System

Navtech’s digital COFDM downlink system is composed of several core components, specifically designed for demanding airborne applications. All equipment is proven and meets accepted specifications for aircraft use. The system provides the latest available technology for robust and secure digital transmission of full resolution, full frame rate video pictures from airborne platforms. The system is in use by both security and broadcast operators. A wide range of compatible ground receive systems are available to meet any operational requirements for short, medium or long range reception.

 Integrated Transmitter Module

Outline Specifications

a) Integrated Transmitter Module NTS-CT2436TX-H3

A compact unit which integrates video interfaces, M-PEG encoding, COFDM modulation and linear power amplification into a single package. The unit meets RTCA/DO160 standards for EMC and mechanical robustness and has also met Eurocopter’s approval standards for EC135 helicopter integration.

Inputs : 2 x analogue video ( PAL / NTSC )

Digital video (ASI or SDI) – optional
70 MHz IF – optional
Audio
GPS

Outputs: RF: up to 10W output ( selectable Hi / Lo power ) 

3.3 – 3.6 GHz 
Video monitor (analogue composite)

Encoding: M-PEG-2 4:2:0 MP@ML 1.5 to 15 Mbit/s

M-PEG-2 4:2:2 P@ML 1.5 to 20 Mbit/s – optional

Modulation: Coded Orthogonal Frequency Division Multiplexing ( COFDM )

6 , 7 or 8 MHz bandwidth, QPSK or 16 QAM modulation
Selectable Guard Interval and FEC
Fully DVB-T compliant
Secure, user-selectable digital encryption

Physical: Dimensions ( W x D x H ): 151 x 230 x 207 mm

Weight: 5.79Kg

Power: Voltage requirement : 26 – 30 V DC ( 28V typical ) via MIL connector

Power consumption: 160W @ +39dBm output

Environmental: Operating temperature: -20 to +50 deg C

Full thermal management via redundant integrated cooling fans

b)  Remote Control Panel  NTS-DTX-RC-H

A small, lightweight unit designed for cockpit mounting. Connects directly to (and powered by) the Integrated Transmitter and provides the following functions:

• Channel selection
• Power on / off / standby
• Video, Antenna, Output power monitoring / alarm
• Selectable output power
• Selectable video source
• Selectable Encryption

Physical :             

Size:   100 x 110 mm
Weight:  240g

c)  Transmit Antenna  NTS-ANT-LC05-H

A variety of antennas are available to suit different installation and performance requirements. Mounting can be directly to the aircraft or via an actuator mechanism.

A typical specification for use in helicopter applications ( as shown in photograph ) is :

• Gain:  5dBi
• Polarisation: circular
• Weight : 0.8Kg
• Size: 206 x 104 mm
• Wind loading: 4.0Kg @ 100mph
• Connector : N-type
• Power : 10W
• Temperature : -20 to +50 deg C

 NOTE:  Navtech Systems Limited has a policy of continuous product development. The data provided above should therefore be used for guidance purposes only.