干线放大器，简称干放，是在功率变低而不能满足覆盖要求时的信号放大设备。当信号源设备功率难以达到覆盖要求时，该设备可以放大信号源（一般是微蜂窝）的功率，以覆盖更多的区域
An amplifier, or dry amplifier for short, is a signal amplification device when the power becomes low and cannot meet the coverage requirements. When the power of the source device is difficult to meet the coverage requirements, the device can amplify the power of the signal source (usually a small cell) to cover more areas
LGT-420M400M干线放大器主要用于无源室内分布系统中补偿由于信号传输和分配而引起的功率损耗。干线放大器为有源器件，在采用干线放大器的室内分布系统中需要考虑干放的噪声系数对于分布系统下行的灵敏度影响和对于整个分布系统上行的噪声抬高。
The LGT-420M400M trunk amplifier is mainly used in passive indoor distribution systems to compensate for power losses due to signal transmission and distribution. The trunk amplifier is an active device, and the influence of the noise figure of the dry amplifier on the sensitivity of the downlink of the distribution system and the noise elevation of the uplink of the entire distribution system need to be considered in the indoor distribution system using the trunk amplifier.
当射频信号进入干线放大器输入端后,经过输入增益电平调节固定斜率均衡和斜率调节,以补偿信号在干线传输中的损耗,使其经过调试后进入模块放大
When the RF signal enters the input terminal of the trunk amplifier, the input gain level is adjusted by the fixed slope equalization and slope adjustment to compensate for the loss of the signal in the trunk transmission, so that it enters the module for amplification after debugging
干线放大器是各种发射机重要的组成部分，在发射机的前级电路中，调制震荡电路所产生的射频电路功率很小，经过三级射频放大处理即一缓冲级、中间放大级、末级功率放大级，获得足够的射频功率以后，才能馈送到天线辐射出去。
Trunk amplifier is an important part of various transmitters, in the pre-circuit of the transmitter, the power of the RF circuit generated by the modulation oscillation circuit is very small, after the three-stage RF amplification treatment, that is, a buffer stage, the middle amplification stage, the last power amplification stage, after obtaining enough RF power, it can be fed to the antenna to radiate out.
射频单元模块化，独立的信号屏蔽腔体，上下行信号在主机内部完全隔离，防止主板信号外泄造成内部自激干扰，采用华为同一供应商器件，每一级放大电路都经过优化调试，指标好寿命长。
The FILER filter technology for optical transceiver color effectively reduces noise radiation, using imported high-quality filter chips, three-stage filtering to reduce radiation generation, and will not bring radiation to precision equipment and sick people
放大器彩用FILER滤波技术有效降噪音辐射，使用进口优质滤波芯片，三级过滤减少辐射产生，不会对精密设备及病体人群带来辐射
The interface side of the optical transceiver is equipped with uplink and downlink gain adjustment buttons, so that engineers can adjust the reasonable uplink and downlink signal gain value through the on-site antenna feeder coverage and user needs to achieve the best signal coverage effect.
有效过滤放大器在放大信号时放大的噪音及杂音，消除不良信号，带来更好的通讯体验
The optical transceiver is equipped with a display screen and multiple indicator lights. The operating status of the equipment and the signal input and output power are provided for the engineer's reference through the display screen. The external panel adjusts amplifier gain, uplink and downlink signals, and more.
信号放大器配备显示屏及多个指示灯。设备运行状态及信号输入输出功率通过显示屏供工程师参考。外置面板可调节放大器增益、上下行信号等。
The optical transceiver has a built-in data acquisition and storage function, which can upload the current equipment running status and signal information to the background through the feeder of signal transmission, and the working status of all optical transceivers in the system can be clearly seen on the background server.
| 参数项目 | 上行 | 下行 |
|---|---|---|
| 产品型号 | DGT-420M | |
| 系统适应 | DPMR,DMR,PDT,NXDN，TETRA | |
| 频率范围 | 410.5~412.5MHz | 420.5~422.5MHz |
| 输出功率 | 0 dBm | ≥18 dBm |
| 增益 | ≥25dB | ≥25 dB |
| 带内波动 | ≤3.0 dB | ≤3.0 dB |
| 驻波比 | ≤1.3 | ≤1.3 |
| 噪声系数 | ≤3 dB | ≤3 dB |
| 射频功率范围 | -90到-110dbm | -90到-110dbm |
| 重量 | 5kg | |
| 外型尺寸(W*H*D) | 483*273*70 | |
| 材质 | 纯铝合金 | |
| 防水防尘 | IP58 | |
| EDS(静电防护等级) | IEC 61000-4-2(Level 4)±8kV(接触放电)±15kV(空气放电) | |
| Parameter items | Uplink | Downlink |
|---|---|---|
| Product model | DGT-420M | |
| System adaptation | DPMR,DMR,PDT,NXDN，TETRA | |
| Frequency range | 410.5~412.5MHz | 410.5~412.5MHz |
| Output power | 0 dBm | ≥35 dBm |
| gain | ≥25 dB | ≥25 dB |
| In-band fluctuations | ≤3.0 dB | ≤3.0 dB |
| VSWR | ≤1.3 | ≤1.3 |
| Noise figure | ≤3 dB | ≤3 dB |
| RF power range | -90arrive-110dbm | -90arrive-110dbm |
| weight | 5kg | |
| Dimensions(W*H*D) | 483*273*70 | |
| Material | Pure aluminum alloy | |
| Waterproof and dustproof | IP58 | |
| ESD protection level | IEC 61000-4-2 (Level 4) ± 8kV (contact discharge) ± 15 kV(air discharge) | |
