High-end measuring instruments are composed of many electronic components. During the working process, the heat generated by the electronic components converges, causing the internal temperature of the instrument to rise, resulting in a decrease in the accuracy of the instrument. How does a high-end measuring instrument solve the effect of temperature on its own accuracy? 1. Influence on diode volt-ampere characteristics When the ambient temperature rises, the forward characteristic curve of the diode will shift to the left and the inverse characteristic curve will move down, as shown in Figure 1. At room temperature, the forward voltage drop is reduced by 2~2.5mV for every 1°C increase in temperature; the reverse current is approximately doubled for every 10°C increase in temperature. It can be seen that the characteristics of the diode are sensitive to temperature. Figure 1 volt-ampere characteristics of the diode 2. Influence on transistor input and output characteristics Due to the thermal sensitivity of semiconductor materials, the parameters of the transistors are almost always temperature dependent. Effect of temperature on input characteristics: Similar to diode volt-ampere characteristics, when the temperature rises, the forward offset will shift to the left, and vice versa, as shown in Figure 2. The effect of temperature on the output characteristics: as shown in the solid line in Fig. 3, the broken lines show the characteristic curves at 20 °C and 60 °C, respectively. It can be seen that when the temperature rises, the collector current increases due to the left shift of the input characteristics. Figure 2 Effect of temperature on transistor output characteristics Figure 3 Effect of temperature on transistor input characteristics Among the many factors that cause the static working point to be unstable, the influence of temperature on the transistor parameters is the most important. The so-called stable static working point suppresses the temperature drift, which usually refers to the static collector current and tube voltage drop of the transistor when the ambient temperature changes. Basically unchanged, it must rely on the change of the base electrode current to offset the change of the collector current. It is common to use DC negative feedback or temperature compensation to make the base current change opposite to the collector current when the temperature changes. Depending on the purpose and precision of the equipment, some require preheating, some do not require preheating, and the equipment is preheated for thermal stability of the internal electronics. Capacitors, inductors, transistors, etc. in the circuit reach a steady state and require a certain amount of time. They must be preheated to reduce the measurement error. The more precise the equipment, the longer the preheating time. How can the Zhiyuan Electronic Power Analyzer make the measurement results more accurate: 1. Preheat the instrument before using the instrument; 2. Before the measurement starts, the zero adjustment operation is required. Zero adjustment refers to the state in which the input signal is zero in the internal circuit of the power analyzer, and the calculation result in this state is set to the zero level in the numerical sense. the process of; 3. Choosing the right range, update rate, and synchronization source is critical to the measurement accuracy of the power analyzer. For example, when the update period is less than the measured signal period, as shown in FIG. 4 below, the data in the entire update period becomes the measurement interval, and the sample data in the entire update period will be averaged, thus affecting the accuracy of the measurement result. In this case, it is necessary to increase the update period so that the measured signal containing more cycles enters the measurement interval; Figure 4 update cycle comparison 4. Reduce the influence of stray capacitance on the measurement result, because there is insulation relationship between the instrument case and the shielding box of the internal measurement circuit, so there is stray capacitance between the two, and the current measurement circuit is connected to the low voltage side, such as As shown in Figure 5, when the current input terminal of the instrument is connected to one end close to the ground potential of the power source, the influence of stray capacitance on the measurement accuracy can be effectively reduced; Figure 5 wiring diagram 5. To reduce the influence of power loss, in the case of measuring large current, the voltage measurement loop needs to be connected to the side close to the load. The result measured by the current measurement loop is the sum of the current flowing through the load and the voltage measurement loop. The measurement error is only It is the current flowing through the voltage measurement loop. In the case of measuring small current, the current measuring circuit needs to be connected to the side close to the load. The result measured by the voltage measuring circuit is the voltage of the load voltage and the current measuring circuit, and the measuring error is only the voltage across the current measuring circuit; As shown in Figure 6. Figure 6 Wiring diagram at different currents At the same time, Zhiyuan Electronics' PA power analyzer adopts 100M synchronous clock with high stability temperature compensation to ensure the phase synchronization of each channel of ADC sampling, and the phase error of voltage and current is within 10 ns. In the module control unit of the host part, we use a 100M synchronous clock with high stability temperature compensation. This clock signal will be sent to the ADC of each channel to ensure the phase synchronization of the ADC sampling, the voltage between the single channel and the channel, The current error can be guaranteed within 10 ns, and the U and I angles are introduced into the instrument itself to reduce the error, ensuring the active power and power factor measurement accuracy! There are many problems in the industry that the power factor is over 1, or too low to be accurately measured. It has a great relationship with the introduction error and test method of the instrument itself. Before the introduction of Zhiyuan Electronic Power Analyzer, the early instruments basically relied on post-calibration instead of hardware synchronous clock source, which was due to advances in electronic technology! As shown in Figure 7. Figure 7 PA power analyzer architecture Can you boost your WiFi signal with outdoor 4G CPE? 4G Outdoor Cpe,4G Lte Outdoor Cpe Router,4G Lte Outdoor Cpe,Outdoor 4G Lte Cpe Router Shenzhen MovingComm Technology Co., Ltd. , https://www.movingcommtech.com
When you travel or go to some remote areas, you may be annoyed by poor reception. Is there any way to get a strong WiFi router signal outdoors in a 4G LTE network? Very good, outdoor 4G CPE router would be a good choice!
What is an outdoor 4G CPE router?
An outdoor 4G CPE router differs from a Wifi-only router in that it needs to be connected to a fiber optic network. The 4G CPE WiFi router can pick up the carrier's 4G LTE network signal and convert it into broadband and Wi-Fi. Just plug in your SIM card with your data plan and enjoy a stable and reliable WiFi signal with family and friends. This Outdoor CPE can be used in harsh environments. If you install your router outside or near a window in an area with a weak 4G signal, your device can receive a better 4G signal.
Second, what are the characteristics of outdoor 4G CPE router?
1. Better network for ODU and IDU
4G CPE outdoor routers include an outdoor unit (ODU) and an indoor unit (IDU). Help your device receive the best outdoor cellular signal through the ODU, and connect to the indoor WiFi router through the network cable to experience better network speed. As shown in the figure below, an outdoor LTE CPE (ODU) is installed outdoors and connected to an indoor Wi-Fi router (IDU) via a network cable. The entire 4G device is powered by POE. This data will be transmitted over the same Ethernet cable, eliminating the need to connect the ODU to a power outlet.
2. High-speed multi-user available
The outdoor 4G CPE features a built-in 4G LTE modem and a 5dBi high-gain antenna. LTE CAT4, download speeds up to 150Mbps, WiFi speeds up to 300Mbps, can connect 32 users at the same time. The high-gain antenna of the outdoor 4G CPE router enables it to have higher power and stronger signal transmission and reception capabilities than mobile phones. Therefore, the CPE router can receive the signal. If your phone can't receive a signal in some areas. Sometimes you also use your phone as a hotspot to share Internet access with your friends, right? Similarly, this 4G LTE CPE router allows 32 users to connect to WiFi at the same time, allowing more users to connect and receive a better signal than a phone sharing hotspot. In addition, the IDU has four Lan ports and can be connected to the device through network cables, which is also a backup mode of the Internet.
3. Excellent outdoor performance and design
On the one hand, outdoor LTE CPE is waterproof, UV resistant and corrosion resistant. It can be used at -20℃~60℃ operating temperature. Therefore, it is ideal for outdoor deployment. On the other hand, there are a variety of installation methods. CPE can be mounted on Windows or walls by mounting brackets. It is also possible to attach it to the antenna mast. In addition, the signal strength is displayed through the LED indicator to facilitate users to find the best location to get a better 4G signal.
4. Support different frequency bands
Outdoor 4G CPE supports a variety of frequency bands, including LTE-FDD, LTE-TDD, 3G WCDMA, and 2G GSM network bands. Meet the needs of different frequency bands in different regions and make full use of network resources.
5. Convenient management of CPE
Start the Web browser to log in to the Web management page. You can configure and manage the CPE easily. The web management system supports Linux. Provides functions such as WebUI management, Telnet, SSH terminal system status monitoring, NTP client, synchronization between devices and the system clock network, and configuration file import and export.
6. Applicable to various application scenarios
CPE is designed to provide ISP or operator with 4G LTE outdoor wifi router to facilitate network connection, whether at home, or in enterprises and remote areas, to bring users a wonderful network experience.
All in all, an outdoor 4G CPE router is an excellent choice for connecting to the Internet in remote areas and places where the signal is weak, the wired network is unreliable, or there is a lack of reliable WiFi. It's worth deploying outdoor CPE in rural, coastal, boat, caravan, campsite and remote areas to enjoy the best network speeds and outdoor activities! It can even reduce complex cabling deployments for home networks without the need to install a wired fiber network.