Antenna sensitivity is its ability to receive weak radio signals. It is measured in microvolts. The quality of the receiver's performance largely depends on the antenna sensitivity. As practice shows, it is not sufficient and then it should be increased.
Instructions
Step 1
As you know, a receiving antenna converts the energy of a high frequency electromagnetic field into electrical vibrations. There are two types of radio receiving antennas - subscriber and professional. The main characteristic of antennas is the resonant gain, measured in decibels. So, for example, the flexible antenna of the Maycom SH-27 radio station has a resonance gain of 15 dB, while a similar antenna belonging to a portable radio station has 20 dB. A difference of 5 dB can increase the broadcast range by up to 30%. It is enough to connect a wire counterweight to the standard antenna of the radio station, as the radio communication range increases by 1.5-2 times.
Step 2
Antenna sensitivity increases with an increase in its size - length and thickness. However, today you can find small compact antennas with a fairly high sensitivity. In some cases, to increase it, it is proposed to use a spherical antenna, since it has a large cross section for interaction with the gravitational field, since it has a large mass.
Step 3
The quality of the radio signal is greatly influenced by the terrain. Reflecting from various obstacles, it is caught by the antenna in a strongly weakened form. If you have high-quality radio equipment, then to ensure stable radio communication, you can use two spatially spaced receiving antennas and two receiving paths. In this case, one antenna will always hedge the other if an attenuated signal came to that one.
Step 4
A weak radio signal causes poor picture quality on television receivers. This problem can be solved with the help of an antenna amplifier, which significantly increases the sensitivity of the antenna. To increase the sensitivity of the radiotelephone receiving devices, you should first adjust the receiving path and then introduce an additional UHF cascade at the input of the receiving device.
