Recently, a news that “Luoyang Unicom reduces the energy consumption of 5g base station through deep sleep of AAU” has caused a heated discussion. Many users worry that 5g base station sleep may affect their use of 5g network. 5g package is not in name.
In this regard, a number of experts interviewed by the reporter of China Economic Daily and China Economic Net said that 5g base station dormancy is not a shutdown, which has little impact on users. It is a way for operators to reduce energy consumption in the case of low traffic. However, this matter has brought the high cost of 5g network operation electricity into the public view.
Why does 5g base station sleep
According to the public information, China Unicom Luoyang Branch has recently started the deep sleep function under no-load state for three different base station radio frequency unit (AAU) devices that have been connected to the network at different times, so as to achieve the purpose of energy consumption control of intelligent base station equipment. For example, for the sites that have not carried out single station verification or have completed single station verification, the AAU deep sleep function will be turned on in full time; For the site being verified by a single station, turn on the AAU deep sleep function in different periods (21:00 to 9:00 the next day).
So, what is AAU deep dormancy? Li Fuchang, deputy director of Wireless Research Department of China Unicom Network Technology Research Institute, introduced that the AAU no-load state deep sleep function refers to that when the base station service is in a long idle state, because there is no 5g user access, the AAU equipment can turn off most of the active equipment power supply and enter the sleep state, so as to achieve the purpose of reducing the AAU no-load power consumption.
Li Fuchang explained that because 5g base station AAU equipment supports 64 channels or 32 channels, a large number of active devices, baseband processing units and other devices are added to 4G equipment, resulting in a significant increase in no-load power consumption of this type of equipment. Compared with 4G, 5g bandwidth is increased by 5 times, and power consumption is increased. It is understood that the typical power consumption of 5g macro station single system is two to three times that of 4G base station. Among them, the increase of AAU power consumption is the main reason for the increase of 5g base station power consumption. Previously, China tower company compared the equipment of Huawei, ZTE and Datang at a forum. The results showed that the typical power consumption of 5g base station was about 3500 watts, and that of 4G system was 1300 watts.
Pan Juan, deputy director of Taier System Laboratory of China Academy of information technology, said in an interview with China Economic Daily and China economic net that 5g network performance improvement will put forward higher requirements for many aspects of the system, such as higher requirements for system computing capacity, transmission capacity, heat dissipation capacity and supporting air conditioning cooling capacity, and correspondingly the overall energy consumption will also increase.
“It is a trend of network management refinement to let the device in no-load state enter deep sleep.” Fu Liang, an independent Telecom analyst, believes that the energy-saving effect can be achieved by using artificial intelligence scheduling algorithm to turn off the power supply of some equipment at low rate and low traffic. This approach has little impact on users, but can significantly reduce operators’ electricity charges and other maintenance costs.
Fu Liang also said that compared with the peak period, when the base station is normally turned on, the energy consumption of the base station does not decrease much in the middle of the night every day, but the actual energy consumption of users is very low, and most of them are “invalid energy consumption”. In addition to further reducing the unit energy consumption of base stations, how to reduce this “invalid energy consumption” has also become the focus of operators and equipment providers.
Will users be affected
So, will this kind of deep dormancy affect the user experience? In this regard, Li Fuchang said that the deep sleep function of 5g base station AAU is turned on during idle business hours, and the operators will judge according to real-time data, so as to realize the intelligent management of 5g network power consumption. At the same time, the operator will keep at least one network to ensure the normal business of users. If 5g traffic suddenly increases, AAU devices can also be quickly awakened through the network management platform.
“Different from turning off the street lights, there is no strict schedule for the base station to enter deep sleep. The premise of sleep is that the current device is in the state of no use or the traffic volume is lower than a certain value.” Fu Liang said that base station dormancy and complete shutdown are two completely different states. Once the conditions are met, you can wake up at any time and let the base station return to normal use.
However, experts also admitted that the current 5g network coverage is small, 5g users are still small, and some simple operations will be adopted in the operation and maintenance process. With the increase of the number of users and the increasing demand of users for the network, the operation and maintenance management of operators will be more and more sophisticated and intelligent.
“This dormancy policy is also constantly adjusted. As the number of users accessing 5g network increases, the operators will gradually shorten the dormancy time until it is completely cancelled and replace it with other network optimization methods.” Fu Liang said.
Fu Liang also said that different from the 5g service for ordinary consumers, this kind of base station dormancy has less impact on 5g industry applications, because the industry application demand curve is obvious, operators can adjust the use of base stations according to the demand, so as to reduce power consumption as much as possible without affecting the use. In addition, under the independent network, if the automatic driving and automatic control have been widely used, the 5g network in the involved area will adopt a more intelligent scheduling mode.
Reducing consumption and increasing efficiency is the key
The high cost of 5g base station construction and operation has always been the industry pain point. Previously, operators have publicly said that the market’s worries about 5g include three points, namely “three 3S”: the number of 5g base stations may be three times more than that of 4G; The power consumption of each 5g base station is three times that of 4G base station; The price of a 5g base station may be three times that of a 4G base station.
Pan Juan said that the frequency of 5g is higher than that of 4G. According to the technical principle, the higher the frequency is, the greater the wireless transmission loss is, the smaller the coverage radius of base stations is, and the more base stations are needed for the same area. In addition, according to the bidding data of operators obtained through public channels, the current purchase price of 4G base station is about 80000 yuan to 100000 yuan / station, and the overall average unit price of 5g outdoor macro station is about 144000 yuan / station.
It is understood that the electricity charges of communication base stations are currently paid by China’s tower operators to the power sector. The person in charge of China Tower introduced to the reporter that about 80% of the built 5g power station is directly supplied by power grid enterprises, and about 20% is transferred power supply (supplied by main bodies other than power grid enterprises such as property companies). The average price of transferred power station is significantly higher than that of direct power supply. At present, China Tower is cooperating with three telecom enterprises, on the one hand, actively striving for the state’s preferential policies for 5g network electricity charges, on the other hand, vigorously promoting the work of “changing the location of power supply station to direct”. It is estimated that by the end of 2020, no less than 50% of the transferred power stations will be converted to direct power supply, which is expected to save about 1.5 billion yuan of electricity annually.
In order to promote the construction of 5g network, various regions have introduced policies to reduce the electricity cost of telecom enterprises. For example, Shanxi proposes that from 2020 to 2022, for 5g base stations after participating in market transactions, the part of the paid electricity fee exceeding the target electricity price by 0.35 yuan / kWh shall be given corresponding support at the provincial, municipal and county levels according to the ratio of 5:2:3, and the total amount of provincial financial funds used for 5g base station electricity price subsidy shall not exceed 50 million yuan per year. According to the preliminary forecast of Shanxi iron tower, the above subsidy can reduce the unit price of 5g base station by about 30%. Guangdong proposes to speed up the transformation of power supply. The allocation of transformation investment takes the low-voltage metering device beside the user’s red line as the dividing point. The power supply side of the dividing point is invested by the power supply department, and the load side of the dividing point is invested by the user.
“With the scale construction of 5g network, the corresponding power cost will also increase. In the initial stage of construction, it is very important to strengthen the power supply guarantee of 5g infrastructure through policy support. For example, we should implement preferential policies for 5g base stations and computer rooms, reduce the electricity price of 5g infrastructure through market competition, further standardize the charges for power transfer, and promote the transformation of qualified communication infrastructure from power transfer to direct power supply. At the same time, it also encourages the industry to reduce costs and increase efficiency through technology upgrading and network optimization to promote development. ” Pan Juan said.
In an interview with reporters, the relevant person in charge of China Telecom also said that it is promoting the industrial chain to further reduce the power consumption of 5g base stations in technology, such as using lower power processing chips and carrying out energy-saving control through artificial intelligence algorithms. At the same time of the current network deployment, according to the local environment, the number of users density to determine the base station transmit power configuration and the number of transmit and receive antennas, through flexible selection of base station configuration to reduce power consumption.