Rainbow Electronics ATA5812 - Manual (Page 11)

11
ATA5811/ATA5812 [Preliminary]
4689B–RKE–04/04
Sensitivity versus
Supply Voltage,
Temperature and
Frequency Offset To calculate the behavior of a transmission system it is important to know the reduction
of the sensitivity due to several influences. The most important are frequency offset due
to crystal oscillator (XTO) and crystal frequency (XTAL) errors, temperature and supply
voltage dependency of the noise figure and IF filter bandwidth of the receiver. Figure 8
shows the typical sensitivity at 433.92 MHz/FSK/20kBaud/
±
16 kHz/Manchester versus
the frequency offset between transmitter and receiver with T
amb
= -40°C, +25°C and
+105°C and supply voltage VS1 = VS2 = 2.4 V, 3.0 V and 3.6 V.
Figure 8. Measured Sensitivity 433.92 MHz/FSK/20 kBaud/
±
16 kHz/Manchester versus Frequency Offset, Temperature
and Supply Voltage
Table 3. Measured Sensitivity FSK,
±
16 kHz, Manchester, dBm, BER = 10 -3
RF Frequency
BR_Range_0
1.0 kBaud
BR_Range_0
2.4 kBaud
BR_Range_1
5.0 kBaud
BR_Range_2
10 kBaud
BR_Range_3
20 kBaud
315 MHz -110.0 dBm -110.5 dBm -109.0 dBm -108.0 dBm -107.0 dBm
433.92 MHz -109.0 dBm -109.5 dBm -108.0 dBm -107.0 dBm -106.0 dBm
868.3 MHz -106.0 dBm -106.5 dBm -105.5 dBm -104.0 dBm -103.5 dBm
Table 4. Measured Sensitivity 100% ASK, Manchester, dBm, BER = 10 -3
RF Frequency
BR_Range_0
1.0 kBaud
BR_Range_0
2.4 kBaud
BR_Range_1
5.0 kBaud
BR_Range_2
10 kBaud
315 MHz -117.0 dBm -117.5 dBm -115 dBm -113.5 dBm
433.92 MHz -116.0 dBm -116.5 dBm -114.0 dBm -112.5 dBm
868.3 MHz -112.5 dBm -113.0 dBm -111.5 dBm -109.5 dBm
-110.0
-109.0
-108.0
-107.0
-106.0
-105.0
-104.0
-103.0
-102.0
-101.0
-100.0
-99.0
-98.0
-97.0
-96.0
-95.0
-100 -80 -60 -40 -20 0 20 40 60 80 100
Frequency Offset (kHz)
V
S
= 2.4 V T
amb
= -40°C
V
S
= 3.0 V T
amb
= -40°C
V
S
= 3.6 V T
amb
= -40°C
V
S
= 2.4 V T
amb
= +25°C
V
S
= 3.0 V T
amb
= +25°C
V
S
= 3.6 V T
amb
= +25°C
V
S
= 2.4 V T
amb
= +105°C
V
S
= 3.0 V T
amb
= +105°C
V
S
= 3.6 V T
amb
= +105°C
Se
n
s
it
iv
it
y
(
d
Bm)