User's Manual

B-2 Spread Spectrum Radio System User’s Manual
March 2001
Functional
Specifications
The radio operates in the license-free 2.400- to 2.4835-GHz ISM
(Industrial, Scientific, Medical) frequency band and is capable of two
data rates
• DBPSK Differential Binary Phase Shift Keying 1 Mb/s
• DQPSK Differential Quadrature Phase Shift Keying 2 Mb/s
Tables B.1 through B.4 list the radio module specifications:
Table B.1 Radio Supply Power
Specification Typical Unit
Power Voltage Input Range (acceptable) 9–38 volts DC
Radio Module Input Voltage from Hub (controlled via
Hub)
24 volts DC
Radio Module Power (receive mode only) 1.43 watts
Radio Module Power (full 98% TX duty cycle) 4.7 watts
Radio Module Power (typical 20% duty cycle)
a
2.1 watts
a. Power = 1.43 + (3.4 ∗ duty cycle) watts
Table B.2 Radio RF Performance and Operation
Specification Typical Unit
Output Power Range 2–30 dBm
Output Power Resolution (8-bit DAC) 256 steps
TX Distance Range (based on 2–30 dBm) 0.3–8.0 miles
B.E.R. 1 × 10
-6
bits
Processing Gain (per 11-bit chipping code) 10.4 dB
Image Rejection 80 dB
Adjacent Channel Rejection >35 dB
Receiver Noise Figure 7 dB
Channel Noise (N=kTB where B=2 MHz despread) −110.97 dBm
Signal-to-Noise Ratio (SNR-E
b
/N
o
∗ R/B
T
) 11.1 dBm
Receiver Sensitivity (= noise floor + SNR) −92.87 dBm