1. Wireless Device status machine (the Radio)The network wireless devices in a typical 3G network include the following three energy consumption states:1. Full power: Allows the device to transfer data at the fastest rate when a network connection is active. 2. Low power: An intermediate state that uses 50% of the energy loss in full power state. 3. Standby: (standby) There is no energy consumption state when the network is in active state. The status switch diagram for three status views is as follows:
If the device is in full power and consumes the most energy, if the network transmission is still 5 seconds in this state, the device will transition from full power to low power, and if the device needs network access at this time, it will take 1.5 seconds from the low Power status transitions to full power state. If the device is in the low power state and the network transmission is stationary for 12 seconds, the device transitions from the low power state to the standby state, and if the device in the Standy state needs network access, the device sends the standby state directly to the full power state. This process takes 2 seconds.The wireless device state machine is related to the network (2G,3G,LTE,ETC.) used by the device, and also to the network operator. However, for all wireless network devices, the above general rules are common. This mechanism is very efficient for typical web browsing, and after the end of the user's web browsing session, the device is converted to low power or standby state to conserve power.Unfortunately, this mechanism is very inefficient for modern smartphones, because apps on smartphones are accessed from the web in the background and in the foreground.
How 2.APP affects wireless device state machines Every time you create a network connection, the wireless network device will turn into full power state. Like the wireless device state machine described above in a typical 3g network, the wireless network device will be in full power when you are transmitting the network, and there will be an additional time of 5 seconds after the end of the network transmission, while the low power will have a 12 second additional time. In this sense, for a typical 3G device, each network transmission session will have about 20 seconds of high power consumption, to ensure the smooth transmission of the network. In practice, if an application requires 3 network access within 60 seconds and each network access takes 1 seconds, there are two ways to access the network as follows: 1. Three network accesses are performed separately, that is, once accessed once, the device is in the standby state and then accessed again, so that it is accessed three times. 2. Three network access is bundled, that is, a network access to complete 3 network access to transfer the content (in time for power). The two modes of the wireless state machine status graph are as follows:
As you can see, using unbound network transports consumes more power than using bound network access. The specific analysis is as follows:Way One:First time Network access:Network access 1 (seconds) + status switch wait time (5 seconds)+Status Switch wait time (12 seconds)Second network access:Network access 1 (seconds) + status switch wait time (5 seconds)+Status Switch wait time (12 seconds) < Span style= "Color:rgb (0,0,0); Font-weight:normal; line-height:1.5 ">&NBSP; Third network access: Network access 1 (seconds) + status switch wait time (5 seconds) + status switch wait time (12 seconds) sum:
Hight Power (18 sec) + low power (36 seconds) Way Two: One Network access:Network access (3 seconds) + Status switch wait (5 seconds)+ status cut-off wait (12 seconds) +standby (40 seconds) Sum:Hight Power (8 sec) + Low Power (12 sec) +Standby/idle (40 sec) So through the above analysis, if can be bundled together in the network access bundle in a network access, to a certain extent, can save energy.
Wireless Device status machines (the Radio state machine)
