With increasing decrease in energy resources and a continuously growing energy price, energy conservation becomes an important factor considered in the design of wireless communication. However, in a wireless communication system, energy is mainly consumed on a base station. Therefore, an energy conservation technology of the base station is especially important. A basic architecture of the base station is shown in FIG. 1, including a control module, a transmission module, an uplink, and a downlink. The uplink includes an uplink baseband processing module, an uplink carrier module, and an uplink power amplifier module. Similarly, the downlink includes a downlink baseband processing module, a downlink carrier module, and a downlink power amplifier module. In particular, in a distributed base station, the architecture of the base station further includes an interface module configured to implement signal transmission between the baseband processing modules and the carrier modules. To meet energy requirements under a high load, each module of the base station is designed according to a high load standard. As a result, a large number of energy resources are wasted unnecessarily in a low load state where there is a small quantity of traffic volume.
To reduce energy consumption under a medium or low load, a method in the prior art is as follows. Static bias voltage of a power amplifier module and power supply of a radio frequency module are turned off according to output power of the power amplifier module; voltage and frequency of the baseband processing module or a refresh rate of a register are adjusted dynamically according to the quantity of traffic volume. Specifically, for the power amplifier module and the radio frequency module, when the traffic volume of the base station is 0, the power amplifier module does not output power, and the bias voltage of the power amplifier module can be turned off to reduce static power consumption when the power amplifier module does not output power. If there is no traffic in a long period of time, the power supply of the radio frequency module is further turned off to reduce static power consumption of the radio frequency module. For the baseband processing module, the voltage and frequency of the baseband processing module or the refresh rate of the register are adjusted dynamically according to the quantity of traffic volume. For example, dynamic voltage and frequency scaling (DVFS) is used, and a dynamic adjustment policy is formulated in advance; when the traffic volume decreases, the frequency and voltage are reduced to reduce the power consumption of the baseband processing module.
During the implementation process of processing a downlink signal, the inventor discovers that the prior art has at least the following problems. In wireless communication systems such as a Global System for Mobile Communication (GSM) and a Universal Mobile Telecommunications System (UMTS), public signals such as a pilot signal, synchronization signal, and broadcast signal specified in a protocol need to be transmitted continuously. As a result, the power amplifier module outputs power continuously, and the power amplifier module and the radio frequency module cannot be turned off. All submodules in a base station processing module need different voltages or frequencies, and thus the unified adjustment policy must simultaneously meet energy requirements of all the sub modules. Therefore, the power consumption of the base station cannot be reduced effectively.