Figure 5: Fabricated QHA (left)
and its S11 parameter (right)
LOW NOISE AMPLIFIER
Maximum transmit power of radiosonde is limited to 20 dBm [5]. Free
space path loss for operating frequency of 406 MHz and path length of
100 km will be about 124 dB. Therefore to Mini-Circuits ultra-low noise
PSA4-5043+ LNA is used to amplify the received signal. Key
specifications are given in Table 4. More details can be found in part
datasheet.
Table 4: Specification of LNA