KingTone Tetra DMR UHF 400MHz 450MHz Line Amplifer BDA used for Indoor Distributions System (IBS),Basement,Tunnel Coverage
Indoor Distributions System (IBS),Basement,Tunnel Coverage Solution Steps:
1. Installation site engineering survey: Is the base station signal 380-400MHz?
Can the cell phone signal at the tunnel entrance location receive 3-4 signals (field strength should at least have -85dBm or better)? If not, look for a location near the tunnel with good signal as the signal receiving point;
Note: The receiving point must be the position of the receiving antenna, but it is not the position of the repeater. The distance from the receiving antenna to the repeater is not limited (can be near or far), and the customer adjusts itself according to the project;
2, antenna installation
The repeater will have two ports, the BS port is connected to the receiving antenna (toward the base station), and the MS port is connected to cover the antenna (toward the coverage area);
However, in order to avoid the self-excitation of the repeater, the repeater cannot work (severe self-excitation will cause the repeater power amplifier module to burn out), so pay attention to the following two points:
a, the receiving antenna and the covering antenna must be back to the back;
b, the distance between the receiving antenna and the covering antenna is at least more than 50 meters, and the specific distance is adjusted according to the actual situation on site;
c. If the installation process, the distance between the two antennas has reached 80 meters or more, it is impossible to avoid self-excitation. It is recommended that customers add a isolation net between the two antennas (such as a large piece of iron) or use the site conditions to The antenna is isolated (such as a mountain or a large building);
3, according to the coverage area: 500 meters tunnel length to place a remote machine
4, feeder & connector: 1/2″ coaxial cable, length: customers customize according to project needs!
5, if there is a corner in the tunnel, it is recommended to add a two-power splitter to the repeater, pull a feeder, and add a cover antenna to cover;
