Figure 2. Measurement device system of noise filtering capability
Figure 2 introduces the measurement device system. The
RF measurement device of Maxim produces the RF filed
which noise filtering capability measurement needs. RF
anechoic chamber has a shielded chamber, which possesses
ports to power supply and monitor. The measurement device
system consists of:
1. Signal generator: 8kHz-3GHz
2. RF power amplifier (PA): 800MHz-1GHz, 20W
3. Power meter: 25MHz-1GHz
4. Anechoic chamber
5. Field intensity indicator
6. Computer
7. Voltmeter
Signal generator produces the RF modulated signal, and
sends the signal to RF power amplifier. Then the signal is
measured by a directional coupler which connects with the
power meter and monitors the PA output. The computer could
control the frequency, kind of modulation, modulation
percentage, power output and the RF filed we need by
regulating the signal generator. And the field is radiated in
anechoic chamber via antenna. The field is symmetrical,
consistent and repetitive.
The typical case of nest telephone filed is almost 60V/m (4
cm from telephone antenna). The field would be lower away