Wireless Modem With RS485 At 8000bps Air Rate

GDW480 is a flexible wireless data communication module which makes it a suitable unit for various RS485 connectivity uses. It operates in VHF or UHF bands with over the air rate 8000bps.

GDW480 meets both the technical and economical requirements set on wireless communications in a number of SCADA system applications, including remote meter reading (like gas, electricity, heat), Remote control of irrigation systems, remote control of distribution, environmental monitoring, and oil data acquisition and control systems.

Specifications

1. General

(1) Operating frequency range: 400 to 420 MHz

(2) Channel spacing: 25 KHz

(3) Number of channels: 16

(4) ANTENNA IMPEDANCE: 50 Ohm unbalanced

(5) OPERATING TEMPERATURE: -40 to +70℃

(6) FREQUENCY STABILITY TCXO: ±1.5ppm

(7)OPERATIONVOLTAGERANGE: 12V DC ( 11Vdc to 14.5V DC)

(8) STAND-BY CURRENT: 85mA

2. TRANSMITTER

(1) RF OUTPUT POWER: 1.5W to 8W programmable

(2) OUTPUT 2ND HARMONIC: less than –65dB

(3) SPURIOUS EMISSIONS: less than 0.25uW (30MHz to 1GHz)

(4) MAXIMUM FREQUENCY DEVIATION: ±5KHz

(5) REFERENCE OSCILLATOR: TCXO

(6) RF IMPEDANCE: 50 Ohm unbalanced

(7) CURRENT DRAIN: 6.0A @25W output power

(8) FM HUM AND NOISE RATIO: greater than –50dB

(9) AUDIO FREQUENCY DISTORTION: 3% 1KHz for 3KHz deviation

(10) AUDIO FREQUENCY RANGE: 300Hz to 3400Hz ±2dB

(11) TRANSMITTER ATTACK TIME: less than 10ms

2. RECEIVER

(1) TYPE OF RECEIVER:Crystalcontrolled double, super heterodyne

(2) INTERMEDIATE frequency: 45MHz(1st IF), 455KHz(2nd IF)

(3) SENSITIVITY: Better than 0.2uV @12dB SINAD

(4) SQUELCH SENSITIVITY: 0.1uV to 1uV programmable

(5) ADJACENT CHANNEL SELECTIVITY: greater than –70dB

(6) SPURIOUS AND IMAGE REJECTION: greater than –65dB

(7) OUTPUT AUDIO DISTORTION: 3% at 1KHz for ±5KHz deviation

(8) FM HUM AND NOISE RATIO: greater than 40dB

3. Data and Interface

(1) MODULATION: MSK

(2) AIR RATE: 8000bps programmable

(3) INTERFACE BAUD RATE: 1200 / 2400 / 4800 / 9600bps programmable programmable

(4) INTERFACE DATA BIT: 8 bit

(5) INTERFACE PARITY BIT: None / Even / Odd

(6) INTERFACE STOP BIT: 1 bit