Narda-MITEQ
HRT-18G FIBER-OPTIC TRANSMITTER
FEATURES
• 50 MHz to 18 GHz frequency range
• -40 °C to +85 °C operating temperature
• Small size
• Plug-and-play
• No external circuits required
• Field-removable optical attenuator for high-loss installations
• Monitors for optical carrier and laser temperature
APPLICATIONS
• Antenna remoting
• Military, shipboard
• Local oscillator remoting
• Interfacility communication links
• Wideband fiber-optic delay lines
The L3 Narda-MITEQ HRT series of fiber-
optic transmitters is designed to be a high-
reliability, wideband, high dynamic range
product from its initial concept. Some
features that contribute to its reliability are:
• Hermetically sealed KOVAR housing
• Oversized thermo-electric cooler to maintain
laser stability over a wide temperature range
• Internal voltage regulation and reverse
polarity protection
• RFI-shielded
• Field-proven microelectronic circuits and
assembly techniques
The HRT series transmitters are for use
with single-mode optical fiber to create
communication and data links that are
secure and provide end-to-end isolation
from damaging spikes and surges.
50 MHz to 18 GHz
Narda-MITEQ
POWER SUPPLY AND MONITOR
PIN DESCRIPTION
VOLTAGE (VDC)
TYPICAL
CURRENT (A)
NOTEMIN NOM MAX
1 Laser Diode Cooler 3 4 6 0.250
Current increases with case temperature up
to 1.2 A
2 Laser Temperature Monitor -0.5 +0.5 < -0.5 V indicates laser temperature is too high
3 Optical Power Monitor -2.5 -2.0 -1.5
4 Ground, Chassis
5 Laser and Amplier Bias +11 +12 +15 0.39
6 Laser Diode Heater -15 -12 -11
0.01
(0.7 A maximum)
Current will increase as case temperature goes
below approximately 5 °C
Notes: Values with 25 °C baseplate temperature.
The +5 V supply connection does not have an internal voltage regulator or reverse polarity protection in order to
lower heat dissipation due to the potential high current this connection can draw to supply the laser cooler.
ELECTRICAL SPECIFICATIONS
PARAMETERS CONDITION UNITS MINIMUM TYPICAL MAXIMUM
Operating Frequency 3 dB bandwidth 50 MHz 18 GHz
Gain (electrical to optical) dB 10 14 20
Flatness dB, peak-to-peak 4
Noise Figure dB 22 25
Group Delay Peak-to-peak ns 0.12 0.2
VSWR Input 1.7 2.0
Phase Noise 100 Hz offset dBc/Hz -100
Input Power at 1 dB Compression dBm -15 -10
Maximum Input Power No damage dBm +10
Impedance Input Ohms 50
RF Connector Type SMA female (male optional)
Note: Performance is specified at 23 °C, with one meter of fiber.
OPTICAL SPECIFICATIONS
PARAMETERS CONDITION UNITS MINIMUM TYPICAL MAXIMUM
Wavelength
(other options available)
nm 1300 1310 1320
Spectral Width FWHM nm 0.06 0.1
Optical Power in Fiber See note mW 5 7 10
Side-mode Suppression Ratio dB 30 40
Optical Connector Type FC/APC standard, other styles on request
Optical Fiber Single-mode, SMF-28 or equivalent
Note: Units are shipped with a 3 dB optical attenuator installed. This attenuator may be removed by the customer to
overcome excess fiber loss. However, take care not to saturate the receiver.
HRT-18G FIBER-OPTIC TRANSMITTER