Why do optical modules in CPRI applications need to support industrial temperatures

      Because the RRU in CPRI operates in a diverse environment with a large temperature difference span, the optical modules applied to RRUs need to support industrial temperatures.
      The CPRI (Common Public Radio Interface) defines the interface relationship between the base station data processing control unit and the base station transceiver unit. Its data structure can be directly used for remote transmission of data from repeaters, becoming an important component of a remote system for base stations.
      In 4G wireless networks, the two units of CPRI, also known as BBU（Building Baseband Unit ） and RRU (Remote Radio Unit), are required to support industrial temperature for the optical module used in 4G wireless networks. Let's do a simple analysis below.
       ⦁ Schematic diagram of BBU and RRU connection in 4G wireless network
The following is a typical connection diagram of BBU and RRU. The BBU is located in the computer room, while the RRU is usually located on an outdoor iron tower.

Figure 1 Schematic diagram of BBU and RRU connection

      The BBU is located in the computer room and has air conditioning to control the temperature at room temperature; The RRU is located outdoors, with significant changes in outdoor temperature.
      For example, the outdoor temperature in northern China can be as low as -40 ℃, while Mohe City in Heilongjiang once set a record for the lowest outdoor temperature in China: -52.2 degrees Celsius. The highest temperature in areas with high temperatures can reach over 45 degrees Celsius. It is said that the highest temperature in China is in Turufan. Considering that RRU equipment is exposed to direct sunlight, without air conditioning, and the equipment itself can generate heat, the design of the optical module needs to be able to withstand a high temperature of 85 degrees Celsius.

Figure 2 RRU physical diagram

      From the above situation, it can be seen that the optical module operating on RRU needs to support the industrial temperature range (-40 to 85 ℃) in order to ensure the performance of the optical module in extreme outdoor environments.
      From this perspective, it is not difficult to understand why CPRI wireless network optical modules require support for industrial temperatures.
      Moduletek Limited Optoelectronics provides industrial temperature grade optical modules for CPRI applications. We welcome everyone to choose and purchase them.
      If you have any questions about the above content, you can contact us by Email : web@moduletek.com