RACOM RipEX, Руководство пользователя

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4.4.1. Detailed Radio parameters
The very first parameter which is often required for consideration is the receiver sensitivity. Anyone
interested in the wireless data transmission probably aware what this parameter means, but we should
regard it simultaneously in its relation to other receiver parameters, especially blocking and desensitiz-
ation. Today’s wireless communication arena tends to be overcrowded and a modern radio modem,
which is demanded to compete with others in that environment, should have good dynamic range that
is defined by the parameters listed above. Receiver of a radio modem, which is designed purely for
optimum sensitivity, will not be able to give proper performance. However, the main receiver parameters
determining its dynamic range go against each other and a clear trade-off between the sensitivity and
the blocking is therefore an essential assumption. Then, from the viewpoint of a logical comparison,
the consequence of better receiver sensitivity can be easily seen – a lower power level of the blocking
and degradation parameters generally.
Blocking or desensitization values were determined according to the standards EN 302 561 V1.2.1 for
50 kHz channel, EN 300 113-1 V1.7.1 for 25 and 12.5 kHz channels, and ETSI 301 166-1 V1.3.2 for
channel 6.25 kHz.
Tab. 4.8: Unlimited 50 kHz
Unlimited 50 kHz Rx
Blocking or
desensitization [dBm] Sensitivity [dBm] Classification
±10 MHz ±5 MHz ±1 MHz BER 10
-6
BER 10
-3
BER 10
-2
Modulation FEC kbps
-14 -14 -16 -107 -111 -114 2CPFSK 0.75 15.62
-14 -15 -16 -106 -110 -113 2CPFSK 1.00 20.83
-18 -18 -19 -101 -105 -108 4CPFSK 0.75 31.25
-18 -19 -19 -100 -104 -107 4CPFSK 1.00 41.67
-9 -10 -12 -105 -109 -112 DPSK 0.75 31.25
-9 -11 -12 -104 -108 -111 DPSK 1.00 41.67
-3 -4 -4 -100 -104 -107 π/4-DQPSK 0.75 62.49
-4 -5 -5 -99 -103 -106 π/4-DQPSK 1.00 83.33
-8 -8 -8 -94 -98 -101 D8PSK 0.75 93.75
-8 -8 -8 -93 -97 -100 D8PSK 1.00 125.00
-5 -6 -6 -91 -95 -98 16DEQAM 0.75 125.00
-5 -6 -6 -90 -94 -97 16DEQAM 1.00 166.67
Unlimited 50 kHz Tx
26 dB Bandwidth OBW 99% [kHz]
Classification
Emission Modulation kbps
30.6 22.1 24K0F1DBN 2CPFSK 20.83
31.7 23.9 24K0F1DDN 4CPFSK 41.67
51.0 45.1 45K0G1DBN DPSK 41.67
51.0 44.8 45K0G1DDN π/4-DQPSK 83.33
51.3 45.3 45K0G1DEN D8PSK 125
51.0 44.7 45K0D1DEN 16DEQAM 166.67
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