DQT-400XD吸顶天线作为无线对讲系统中前段信号覆盖设备是必不可少的传输介质；信号覆盖的效果取决于吸顶天线的质量及分布合理性。
DQT-400XD ceiling antenna is an indispensable transmission medium as the front signal coverage equipment in the wireless intercom system; The effectiveness of the signal coverage depends on the quality and distribution of the ceiling antenna.
室内全向天线通过楼宇内分布天线系统，将无线对讲系统天馈信号传输到楼内各个角落，达到解决室内信号强度和质量问题。另外，室内全向天线可通过加装干线信号放大器，弥补因馈线损耗损失的能量，扩大室内全向天线主机覆盖范围。
The indoor omnidirectional antenna transmits the antenna feeder signal of the wireless intercom system to all corners of the building through the antenna system distributed in the building, so as to solve the indoor signal strength and quality problems. In addition, the indoor omnidirectional antenna can be equipped with a trunk signal amplifier to make up for the energy lost due to feeder loss, and expand the coverage of the indoor omnidirectional antenna host.
中欧体育吸顶天线采用螺旋形振子 增加信号接触面，信号强度更高，插损低，保留信号，避免物理损耗。清晰辨识 安装简易，全金属底座 高隔离度，杜绝干扰，最大程度确保信号纯净 加固螺栓轴承 轴承加长，增加接触面积，咬合力更强避免脱落，采用优质树脂材质，耐腐蚀。
The Lielong ceiling antenna adopts a spiral oscillator to increase the signal contact surface, which has higher signal strength, low insertion loss, and retains the signal to avoid physical loss. Clearly recognizable Easy to install, all-metal base High isolation, no interference, maximum signal purity Reinforced bolt bearings The bearing is lengthened, the contact area is increased, the bite force is stronger to avoid falling off, and the high-quality resin material is used to resist corrosion.
室内吸顶天线为无源微波器件，中继台发射的电磁波即下行信号是由中继台通过合路平台相关设备及同轴馈线传输至室内天线；对讲机在室内覆盖区域使用过程中也会通过对讲机自带的天线发射相应的电磁波即上行信号，由室内就近的吸顶天线接收通过馈线传输至中继台。
The indoor ceiling antenna is a passive microwave device, and the electromagnetic wave emitted by the repeater, that is, the downlink signal, is transmitted to the indoor antenna by the repeater through the relevant equipment of the combining platform and the coaxial feeder; During the use of the walkie-talkie in the indoor coverage area, it will also emit the corresponding electromagnetic wave through the antenna that comes with the walkie-talkie, that is, the uplink signal, which will be received by the ceiling antenna near the room and transmitted to the repeater station through the feeder.
天线为水平极化方式，具有增益高，匹配性好和宽频带的特点，其具有方向性强、抗干扰等，且外观精美，安装结构方便，适宜长期稳定适用。
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
超高分子量聚乙烯具有300至600万的分子量。具备足够的强度，其他低等聚合产品所不具备耐磨损和抗冲击能力。一体挤压成型是Discovery系列独有的加工工艺
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.
短跳线使用50-3同轴射频电缆，相对较长跳线信号衰减小，减少链路中信号流失，确保室内覆盖更稳定。
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.
中欧体育增加了振子片体外侧周缘的周长，从而增加了电流程度使得工作频段向低频扩展，实现吸顶天线的双频段一体化的设计，简化了吸顶天线的结构，提升了性能。
The perimeter of the outer periphery of the oscillator sheet is increased, so that the working frequency band is extended to the low frequency, and the dual-band integrated design of the ceiling antenna is realized, which simplifies the structure of the ceiling antenna and improves the performance.
| 产品型号 | DQT-400XD | 工作湿度 | 5%~95% |
| 频率范围 | 400-440.450-490MHz | 存储温度 | 5%~95% |
| 增益( dBi) | 2 | 阻抗() | 50 |
| 插入耗损(dB) | ≤1 | 灵敏度(dB) | -128 |
| 回波损耗(dB) | -35 | 线材长度(cm) | 25 |
| 峰值承载功率(W) | 50 | 线材接口 | N型(公头) |
| 信道隔离(dB) | 65 | 质量(g) | 200 |
| 输入端口电压驻波比 | <1.0 | 吸顶面积(cm2) | 226 |
| 输出端口电压驻波比 | 1.25:1 | 防护等级 | IP54 |
| 安装方式 | 吸顶安装 | 外观材质 | 高密度聚乙烯 |
| 固定方式 | 旋扭固定 | 线材 | RG58U |
| 极化方向 | 垂直极化 | 包装尺寸(cm) | 74*35*31 |
| 接口类型 | N-K | 水平面波瓣竞度 | 360 |
| 温度范围 | -30~+60° | 振子材料 | 铝合金 |
| 储存温度 | -30~+60° | 接口位置 | 电缆底部 |
| Product model | DQT-400XD | Operating humidity | 5%~95% |
| Frequency range | 400-440.450-490MHz | Storage temperature | 5%~95% |
| gain( dBi) | 2 | impedance | 50 |
| Insertion Wear (dB) | ≤1 | Sensitivity (dB) | -128 |
| Return Loss (dB) | -35 | Wire length (cm) | 25 |
| Peak Carrying Power | 50 | Cable interface | Type N(M) |
| Channel Isolation (dB) | 65 | Mass (g) | 200 |
| VSWR of the input port voltage | <1.0 | Ceiling Area(cm2） | 226 |
| VSWR at the output port | 1.25:1 | Ingress protection | IP54 |
| Installation | Ceiling mounting | Appearance material | High-density polyethylene |
| Fixation | Twist fixation | wire rod | RG58U |
| Direction of polarization | Vertical polarization | Packing size (cm) | 74*35*31 |
| Interface type | N-K | Horizontal lobe competition | 360 |
| Temperature range | -30~+60° | Vibrator material | Aluminum alloy |
| Storage temperature | -30~+60° | Interface location | The bottom of the cable |
