Chapter 1. Introduction - Javad HPT135 series Operator's Manual

Chapter 1
I
NTRODUCTION
External extra rugged digital high power VHF radio transceiver programmable in frequency
ranges from 138 to 174 MHz. It has GMSK, DBPSK, DQPSK, 4FSK, D8PSK, and D16QAM
modulations with advanced forward error correction and data scrambling. The output power is
programmable from 320 mW to 35 W.
Figure 1-1. HPT135
It takes incoming data, modulates it with GMSK, FSK, PSK or most spectrum efficient QAM
modulation and transmits it at RF power output levels from 25 dBm up to 45 dBm operating in
VHF frequency band 138 to 174 MHz.
The VHF transceiver is also capable of receiving RF signals through a 50 Ohm impedance
external antenna port. These signals are demodulated and output to the JAVAD GNSS receiver.
HPT135 delivers a reliable radio link at up to 38.4 kbps over the air for the 25 kHz channel
spacing, 19.2 kbps for 12.5 kHz, and 9.6 kbps for 6.25 kHz.
The unmatched features of HPT135 include data scrambling, frequency hopping, user selectable
transmit output power level, low power consumption sleep modes, autoscanning for base.
The unit's user settings can be changed through the built-in Command Line interface (CLI), Tracy
Software or through ModemVU.
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