KR20110094452A - Mobile communication terminal for low power paging and control method thereof - Google Patents

Abstract

PURPOSE: A mobile communication terminal for a low power paging is provided to manage a paging slot cycle index by the mobile terminals. CONSTITUTION: A communication amount data storage(102) stores data about communication amount by the time. A slot cycle index determining unit(104) deciphers the communication amount from the communication amount data storage. The slot cycle index determining unit determines the slot cycle index by the deciphered communication amount. A response time control unit(106) controls the response time of the receiving part by the predetermined slot cycle index.

Description

Mobile communication terminal for low power paging and control method thereof {MOBILE COMMUNICATION TERMINAL FOR LOW POWER PAGING AND CONTROL METHOD THEREOF}

The present invention relates to a mobile communication terminal and a control method thereof, and more particularly, to a mobile communication terminal and a mobile communication system for implementing a low power paging method by varying a slot cycle index according to a user's mobile communication terminal usage pattern. will be.

The recent IT trend is, above all, Green IT. Green IT is an environmentally friendly industry that grows faster than other industries and only accounts for 2% of total CO2 emissions, making it an alternative to other carbon-intensive industries. In the mobile phone field, the company aims to implement Green IT by focusing on the power consumption of the multifunctional generation.

Mobile communication terminals, commonly called mobile phones, can be divided into LCD module and lower mechanical part. The lower part is divided into Radio Frequency (RF) Section, Baseband, WM and MSM. The first element of the analog part is an antenna, and the signal transmitted and received through the antenna at the first end of the terminal is full duplexed through a duplex element to separate the transmitted signal from the received signal. In other words, during transmission, the output power of the transmitter power amplifier module (PAM) passes through the duplex to deliver the maximum power to the antenna, and when receiving, the weak RF signal received through the antenna passes through the duplex, It is responsible for transmitting signals to the LNA. In addition, the PAM must amplify the appropriate signal size in consideration of the loss of the duplexes. This is the component that consumes the most power among the circuit components. The phenomenon of heat in the terminal during long-term communication is caused by power consumption of the PAM. Driver Amp uses the signal output from Up Converter (UP MIXER) of transmitter to amplify PAM sufficiently. Transmitted and received RF signals are eliminated unnecessary frequencies, such as noise, through band pass filters such as Rx BPF and Tx BPF. Later, frequency correction is performed through VCO, Phase Locked Loop (PLL), and VC-TCXO. Next, look at the MSM stage, you can look at PMIC (Power Management IC), MSM, MCP. PMIC is an IC that distributes and distributes power supplied to each component of a mobile phone. Without this part, certain features of the terminal may not be available or the entire system may not run. It is possible to ignite parts due to overload, which is very important and can be the basic part of the system.

Power Consumption (mW) Composition ratio (%) Baseband Core 113 12 Baseband Analog 104 11 RF Transceiver 320 33 Power Amplifier 408 42 SRAM 18 2 all 963 100

So far, we have looked at the power lost inside the terminal. Next, the basic power consumption and the power consumption of the terminal call processing process will be described. The call processing process of the terminal is shown in FIG.

First, when the terminal is booted, the terminal enters a mobile station initialization state for receiving a pilot and a sync channel. This initialization of the terminal establishes the state necessary for operation on the memory of the terminal and reads the corresponding information from the EEPROM.

After the terminal completes its own operation, it receives the pilot channel and then receives the necessary system information on the synchronization channel. After that, the terminal transitions to the response waiting state. This means that the terminal processes a voice call or a control signal after providing a condition for internally providing various services such as voice communication. That is, the terminal receives the necessary information on the synchronization channel and then receives and processes the system parameters, or performs an appropriate response to various requests such as a call signal. After the normal operation is completed, if the paging channel is continuously received and the system information (paging channel message) is not received, the initialization starts again. A call state is connected to a paging channel and an access channel through a terminal call signal in a call waiting state and is called a traffic state. In the call state, the call is initialized to reset system time, long code state, and paging channel message that may be missed during the call. We used a CDMA 2000 protocol analyzer to analyze the power consumption of each terminal call processing procedure.

Let's look at the power consumption of each state. Terminal initialization state, which is the first step for the terminal to operate, is shown in FIG. 2. When the terminal is powered on, the Tx power is -52.42dBm and the Rx power is -86.58dBm. After the terminal is connected to the pilot channel, the Tx power temporarily increases by about 60dBm to 14dBm while the Rx power remains unchanged at -86.58dBm.

Looking at the power consumption in the idle state (Idle State) of Figure 3 it can be seen that the Tx power of -49.74dBm, Rx power of -89.25dBm similar to the terminal initialization state is maintained relatively constant. This value changes rapidly as the mobile phone starts a call, as shown in FIG.

In the traffic state, the base station and the terminal are connected, and at that moment, a peak occurs at one Tx power as in the graph above. This means that the Tx power is 8.58dBm and 14.91dBm, respectively, and has an increase of about 58dBm and 66dBm. The Rx power is -79.25dBm and -82.31dBm, which shows a relatively small power increase compared to the Tx power.

We have looked at the power consumption in the internal device and call processing of the terminal. It was confirmed that there is a large power consumption due to the peaking phenomenon when the base station and the terminal are connected before the call starts. The connection between the base station and the terminal is called paging. When a call arrives at a mobile communication terminal, the terminal calls the terminal through a base station control apparatus where the terminal is located. The paging area is a location area most recently registered by the terminal and is stored in a VLR (Visitor Location Register) in the exchange. The detection of the signal through paging is performed by a digital clock when analyzed in a circuit and mainly plays a role in the wireless transceiver stage. Referring to Table 1, it can be seen that power consumption in the internal circuit of the mobile phone is high in the RF stage.

Accordingly, an object of the present invention is to reduce the power consumption of a mobile communication terminal by managing a paging slot cycle index for each terminal without a large load on the mobile communication system.

In another aspect, the present invention is to adjust the slot cycle index to reduce the power consumption of the mobile communication terminal so as not to delay the response time.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention which are not mentioned can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. Also, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

In order to achieve the above object, the present invention provides a mobile communication terminal, comprising: a call amount data storage for storing data about a call amount of a user's time zone, a call amount of a current time from the call amount data storage, and the call amount according to the read call amount. And a response time controller for controlling a response time of the receiver according to the determined slot cycle index.

In another aspect, the present invention provides a method for controlling a mobile communication terminal, the method comprising the steps of: storing data about a call amount for each time zone of a user in a call amount data storage unit, reading a call amount of a current time from the call amount data storage unit, And determining the slot cycle index according to the present invention, and controlling the response time of the receiver according to the determined slot cycle index.

In addition, the present invention is a mobile communication system, a slot cycle index receiving unit for receiving a slot cycle index from the mobile communication terminal and the paging to the mobile communication terminal according to the slot cycle index of the mobile communication terminal received from the slot cycle index receiving unit Another feature is to include a paging power adjuster that adjusts the power of the channel.

The present invention also provides a method for controlling a mobile communication system, the method comprising: receiving a slot cycle index from a mobile communication terminal, and powering a paging channel to the mobile communication terminal according to the received slot cycle index of the mobile communication terminal. It is another feature to include the step of adjusting.

The present invention reduces the power consumption during terminal operation by adjusting the slot cycle index considering the individual characteristics of the user during the paging process between the terminal and the base station. Users can be classified according to call duration and call volume.

Increasing the slot cycle index results in increased power consumption resulting in lower power consumption, but longer call latency. Therefore, through the call pattern analysis, the response time is reduced by making the index small at the time of high call volume, and the power consumption is reduced by making the index large at the time of low call volume.

When the slot cycle index is large, the signal-to-noise ratio of the terminal may be increased by ramping power from the base station to the paging channel. Increasing the slot cycle index increases the response time, which increases or decreases the paging delay by increasing power during paging for the terminal.

According to the present invention, through the call pattern analysis, it is possible to reduce the power consumption of the mobile communication terminal by shortening the index when the call volume is large, thereby increasing the response time, and by increasing the index when the call volume is small.

In addition, according to the present invention, since the terminal does not manage the paging slot cycle index for every terminal but manages its own history and adjusts the index according to time slots, the burden of the mobile communication system is not great.

In addition, according to the present invention, since the terminal determines a new slot cycle index based on the past history information, it is possible to provide a paging slot cycle index suitable for a gradually changing user characteristic.

1 is a flowchart illustrating a call processing process of a mobile communication terminal.
2 is a diagram for explaining power consumption in an initialization state of a mobile communication terminal.
3 is a diagram illustrating power consumption in a standby state of a mobile communication terminal.
4 is a diagram for explaining power consumption in a call state during transmission of a mobile communication terminal.
5 is a diagram for explaining power consumption in a call state when a mobile communication terminal is received.
6 is a block diagram illustrating a configuration of a mobile communication terminal and a mobile communication system according to an embodiment of the present invention.
7 is a flowchart illustrating a control method of a mobile communication terminal according to an embodiment of the present invention.
8 is a view for explaining an example of the call amount data stored in the call amount data storage of the present invention.
9 is a view for explaining the operation of the slot cycle index determination unit of the present invention.
10 is a view for explaining the operation of the response time control unit of the present invention.
11 is a flowchart illustrating a control method of a mobile communication system according to an embodiment of the present invention.
12 is a graph illustrating a relationship between paging power and response time.
13 is a graph illustrating a change in response time according to channel conditions.
14 is a graph illustrating the change of the signal-to-noise ratio according to the change of the slot cycle index under the same channel.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings, It can be easily carried out. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

6 is a block diagram illustrating the configuration of a mobile communication terminal 100 and a mobile communication system 200 according to an embodiment of the present invention. 7 is a flowchart illustrating a control method of the mobile communication terminal 100 according to the present embodiment, and FIG. 11 is a flowchart illustrating a control method of the mobile communication system 200 according to the present embodiment.

The mobile communication terminal 100 includes a storage device 102, a slot cycle index determination unit 104, a response time control unit 106, and a transmission / reception unit 108. The storage device 102 stores data on the amount of call for each time zone of the user (S702). The call volume per time zone may be an average call volume for a unit time. 8 is a view for explaining an example of time zone call amount data stored in the storage device 102. In FIG. 8, the average call volume in the (00:00-01:00) time zone is 5 minutes, the average call volume in the (01:00-02:00) time zone is 0 minutes, and in the (13:00-14:00) time zone. Average call volume is 20 minutes. The slot cycle index determination unit 104 reads the talk amount of the current time from the storage device 102 and determines the slot cycle index according to the read talk amount (S704). 9 is a view for explaining the operation of the slot cycle index determination unit of the present invention. For example, in the case of a user having the call volume shown in FIG. 8, the slot cycle index determination unit 104 allocates a low slot cycle index I ₂₀ for the call quality in the (13:00-14:00) time zone. In the time slots (00:00-01:00) and (01:00-02:00), the higher slot cycle indexes I ₅ and I ₁ are assigned to reduce power consumption. The response time control unit 106 controls the reception end response time of the transceiver unit 108 according to the slot cycle index determined above (S706). The response time controller 106 assigns a longer response time than the normal mode for the same slot cycle index when the user specifies the power saving mode. 10 is a view for explaining the operation of the response time control unit 106. If the slot cycle index is I ₁ , T ₁₁ is assigned as response time in normal mode and I ₁₂ is assigned as response time in power saving mode.

The mobile communication system 200 includes a base station 210, and the base station 210 includes a transceiver 201, a slot cycle index storage 214, and a paging power controller 216. The transceiver unit 212 receives the slot cycle index from the transceiver unit 108 of the mobile communication terminal 100, and the slot cycle index storage unit 214 stores the slot cycle index received from the transceiver unit 212 ( S1102). The paging power control unit 216 reads the slot cycle index of the mobile communication terminal 100 from the slot cycle index storage unit 214 and adjusts the power of the paging channel to the mobile communication terminal 100 accordingly (S1104). ). The paging power controller 216 may increase the power of the paging channel when the slot cycle index received from the mobile communication terminal 100 is large. In addition, the paging power controller 216 may ramp the power of the paging channel to the mobile communication terminal 100 according to the received slot cycle index to increase the signal-to-noise ratio of the mobile communication terminal 100.

The present invention seeks to compensate for unnecessary power consumption by increasing the paging interval to optimize mobile phone power consumption, which is improved by adjusting the paging interval for each user according to the lifestyle of each user. In general, the longer the slot cycle index (Slot Cycle Index) can increase battery life by reducing the power consumption due to the increase in the standby state. However, when the mobile station calls the mobile station, the call connection waiting time is lengthened because the base station does not call right away and waits until the determined slot. The slot cycle index cycle can be changed by both the operator and the subscriber, but specifies a maximum value of N at the operator side. Set to Non Slot Mode if you want reliable use regardless of battery life or want quickness without latency.

In the first experiment, 15 days' worth of data was measured every hour and stored in memory. Based on this data, we analyzed individual behavioral patterns, adjusted the paging slot cycle index according to the patterns, and analyzed how the actual paging interval influences the power consumption. Table 2 analyzes the call patterns of subscribers with different call types, such as housewives, salespeople, and students, before and after improving the power gains resulting from changing slot cycle index values. Table 3 shows the corresponding times allocated to the slot cycle indexes.

index Salesperson housewife student Before improvement AM6-7 2.5 2.5 2.5 1.5 AM7-8 2.5 2.5 1.5 1.5 AM8-9 One 2.5 1.5 1.5 AM9-10 One 2.5 2 1.5 AM10-11 One 2 2 1.5 AM11-12 One 1.5 2 1.5 PM12-13 One 1.5 2 1.5 PM13-14 One 1.5 2 1.5 PM14-15 One 1.5 2 1.5 PM15-16 One 1.5 2 1.5 PM16-17 One 2 2 1.5 PM17-18 One 2 1.5 1.5 PM18-19 One 2 1.5 1.5 PM19-20 One 2 1.5 1.5 PM20-21 One 2 1.5 1.5 PM21-22 1.5 2 1.5 1.5 PM22-23 1.5 2.5 2 1.5 PM23-24 1.5 2.5 2 1.5 PM24-1 1.5 2.5 2.5 1.5 AM1-2 2.5 2.5 2.5 1.5 AM2-3 2.5 2.5 2.5 1.5 AM3-4 2.5 2.5 2.5 1.5 AM4-5 2.5 2.5 2.5 1.5 AM5-6 2.5 2.5 2.5 1.5

index time 0 1.28 0.5 2 One 2.56 1.5 3.8 2 5.2 2.5 7.5

First, salespeople take up most of their time except for the hours of sleep and early morning hours. Also, housewives rarely make calls because they are often at home unless they make a separate appointment. Students rarely spend their time except in the evenings when there is room for them. Through this call pattern analysis, when the call volume is high, the index is shortened to speed up the response time. On the contrary, when the call volume is low, the index is reduced to some extent to slow down the response time, thereby reducing the power consumption. The Korean telecommunications company used the slot cycle index as 2, and in this example divided it to the decimal point.) As a result, the power consumption was 98% for the salesperson, 69.9% for the housewife, The case could be reduced by 75%.

In addition, three researchers who differed greatly in actual currency patterns were selected and distributed according to the slot cycle index, which can reduce the power consumed by the time of day. Also, when the volume of calls is high, the index is made smaller to speed up the response time. On the contrary, when the volume of calls is small, the index is set to some extent to slow the response time. Table 4 analyzes before and after improving the power gain obtained by changing the slot cycle index value.

index A B C Before improvement AM6-7 2.5 2.5 2.5 1.5 AM7-8 2.5 2.5 One 1.5 AM8-9 2.5 2 1.5 1.5 AM9-10 2.5 2 2 1.5 AM10-11 2 2 2 1.5 AM11-12 2 2 2 1.5 PM12-13 1.5 2 2 1.5 PM13-14 1.5 One One 1.5 PM14-15 1.5 2 2 1.5 PM15-16 1.5 2 2 1.5 PM16-17 1.5 1.5 2 1.5 PM17-18 1.5 One 2 1.5 PM18-19 1.5 One One 1.5 PM19-20 1.5 One 2 1.5 PM20-21 1.5 1.5 2 1.5 PM21-22 1.5 2 2 1.5 PM22-23 One 2 2 1.5 PM23-24 One 2 2 1.5 PM24-1 One 2.5 3 1.5 AM1-2 One 2.5 2.5 1.5 AM2-3 1.5 2.5 2.5 1.5 AM3-4 2 2.5 2.5 1.5 AM4-5 2.5 2.5 2.5 1.5 AM5-6 2.5 2.5 2.5 1.5

In the slot cycle index adjustment result table according to the individual call patterns, the response time and power consumption according to the change of the slot cycle index can be confirmed. Check this in a graph is as shown in FIG.

12 is a graph illustrating a relationship between paging power and response time. In FIG. 12, it can be seen that the power consumption decreases as the response time, that is, the slot cycle index increases. (The power consumption at this time was measured in mW.) In general, as the response time increases, the probability of connection failure increases and the probability of error at the cell boundary also increases, so the most important point is to find an optimized point for each user by adjusting a trade off between them. The present invention is a method of increasing the signal-to-noise ratio of the terminal by ramping power in the base station itself. It suggests a means of resolving the trade-offs.

First, the analysis is based on the assumption that the message is transmitted in the (7,4) Hamming Code. The (7,4) hamming code adds 3 bits of redundancy to send 4 bits of message bits. In this case, four bits of message bits and three bits of redundancy bits may be defined in units of one symbol. Therefore, if you send a 12-bit message, it will be sent in three symbols. Response using P _E (message error probability), P _S (symbol error probability), P _B (bit error rate) (hereinafter referred to as BER) The present invention is analyzed by deriving time.

Let T be the time between slots according to the slot cycle index. In this case, the expected response time may be represented by the sum as shown in Equation 1 since each slot is independent as follows.

Analyzing this, since the second term is a geometric distribution, the average response time t is expressed by Equation 2.

In addition, since one error can be corrected in the (7,4) hamming code, the symbol error probability is expressed by Equation 3.

In this case, if the paging slot does not detect the message more than three times, it is regarded as an error, and the message error probability at that time may be expressed as in Equation 4.

Message error probability is affected by the state of the channel. In the experiment, P _E was randomly assumed to have a value of 0.1 to 0.7, and different channel states were assumed. The resulting graph is shown in FIG.

13 is a graph illustrating a change in response time according to channel conditions. In FIG. 13, the response time is a function of two variables, T and P _E , and as the slot cycle index increases or P _E increases, the response time, which is the response waiting time, increases. This means that the call quality is degraded. In addition, if power consumption is minimized by increasing T in the same position and same channel state (P _E is constant), it is a gain in terms of power consumption, but there is a trade-off in which the response time is long and the call quality is reduced. have. This can be seen in the resulting data figures and graphs in Table 5.

P _E P _S P _B 2E _b / N ₀ E _b / N ₀ 0.1 0.0345 0.04361 1.71 0.855 0.2 0.0717 0.06521 1.51 0.755 0.3 0.1121 0.08423 1.38 0.69 0.4 0.1566 0.10276 1.27 0.635 0.5 0.2063 0.12191 1.17 0.585 0.6 0.2632 0.14274 1.07 0.535 0.7 0.3306 0.16681 0.97 0.485

In the next experiment, we will determine the requirements to achieve the same response time by changing the slot cycle index to resolve the trade-off. After the response time spent in the experiment was 0.3, and the slot cycle index is 1.5 (T = 3.8) based on the value (t = 2.4700) when the so under the same call quality regardless of the slot cycle index changes P _S, P We looked at the values of _E and E _b / N ₀ .

14 is a graph illustrating a change in a signal-to-noise ratio according to a change in a slot cycle index under the same channel. As shown in FIG. 14, it can be seen that as the slot cycle index increases, the P _S value gradually decreases to increase the signal-to-noise ratio (here, represented by E _b / N ₀ ). This can be confirmed by changing the y-intercept (P _S ) value as the slot cycle index increases when the same P _B value is given in the above graph. This problem can be solved through power ramping from the base station to the paging channel.

So far, we have devised ways to reduce power consumption in relation to paging. The terminal power consumption is reduced by distributing a paging interval called a slot cycle index according to a call pattern for each user. However, since the slot cycle index has a trade-off that the response time related to the call quality is increased and the call quality is degraded as the value is increased, the power ramping from the base station to the paging channel has been proposed. We looked at the analysis. In addition, the trade-off for increasing the signal-to-noise ratio can be complemented in the same way not only inside the cell, but also at the cell boundary. Communication at the cell boundary results in power attenuation because the distance between the user and the transmitting station is far, resulting in reduced performance in which received power is reduced. In other words, power reduction due to distance increases the error rate, making it difficult to detect an accurate signal and increasing the response time, resulting in a deterioration in call quality. In order to improve such performance degradation, increasing the signal-to-noise ratio of power in the transmission process can improve P _S and P _E by improving BER. As a result, when the paging user receives the information that the cell user is at the cell boundary, and ramps the power to the user, the user can not only reduce the response time but also improve the performance at the cell boundary.

So far, only the case of a single cell has been discussed, but the present invention is not only a case of using a total of three sectors of α, β, and γ in one cell, but also a multi-cell in which several cells overlap. Can also be applied.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

Claims (8)

In the mobile communication terminal,
Call volume data storage unit for storing data about the call volume of the user's time zone,
A slot cycle index determination unit which reads a call amount of a current time from the call amount data storage unit and determines a slot cycle index according to the read call amount;
A response time controller for controlling a response time of a receiver according to the determined slot cycle index;
Mobile communication terminal, characterized in that provided.
The method of claim 1,
Mobile communication terminal, characterized in that the call amount for each time zone stored in the call amount data storage unit is the average call amount for the unit time.
The method according to claim 1 or 2,
The response time control unit allocates a response time longer than the normal mode for the same slot cycle index when the user designates a power saving mode.
In the method for controlling a mobile communication terminal,
Storing the data on the call volume by time of the user in the call volume data storage;
Reading a call amount at a current time from the call amount data storage and determining a slot cycle index according to the read call amount;
Controlling a response time of a receiver according to the determined slot cycle index;
Control method of a mobile communication terminal, characterized in that provided.
In the mobile communication system,
A slot cycle index receiver which receives a slot cycle index from a mobile communication terminal,
Paging power control unit for adjusting the power of the paging channel to the mobile communication terminal according to the slot cycle index of the mobile communication terminal received from the slot cycle index receiver.
Mobile communication system characterized in that it comprises.
The method of claim 5, wherein
And the paging power controller increases the power of the paging channel when the received slot cycle index is large.
The method according to claim 5 or 6,
And the paging power controller ramps power of a paging channel to the mobile communication terminal according to the received slot cycle index to increase a signal-to-noise ratio of the mobile communication terminal.
In the method for controlling a mobile communication system,
Receiving a slot cycle index from a mobile communication terminal;
Adjusting power of a paging channel to the mobile communication terminal according to the received slot cycle index of the mobile communication terminal;
Control method of a mobile communication system, characterized in that it comprises.

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