KR101337181B1 - Apparatus and method for controlling power of a mobile station in a wireless communication system - Google Patents

Abstract

According to the present invention, in controlling power in a mobile terminal, a workload of a modem required to process the received data is predicted based on data amount information on data received from a base station, The amount of power required is determined based on the information about the controller, and the voltage of the modem is controlled by a voltage value corresponding to the determined amount of power.

WiMax, DVFS, Voltage, Frame, Uplink, Downlink, Uplink, Downlink

Description

Apparatus and method for controlling power of a mobile terminal in a mobile communication system {APPARATUS AND METHOD FOR CONTROLLING POWER OF A MOBILE STATION IN A WIRELESS COMMUNICATION SYSTEM}

The present invention relates to dynamic voltage frequency scaling (hereinafter referred to as DVFS), and more particularly, to an apparatus and method for saving power of a battery by converting a voltage and a frequency in a mobile terminal.

A frame including data used in a mobile terminal supporting WiMax (Worldwide Interoperability for Microwave Access) is divided into downlink and uplink, and is referred to as orthogonal frequency division multiple access (OFDMA), which is a multiple access method. The OFDM symbol consists of 1024 subchannels.

The modem used in the mobile terminal or laptop adopting the above technology consumes power when downloading or uploading a phone call or data. When the application is run, power is consumed according to the amount of work required by the application. It consumes a small amount of power even when it is in a standby state not running an application. The modem card of the laptop can be USB dongle type, PC card, Cardbus, PCI express type.

Therefore, the present invention, which was devised to solve the problems of the prior art operating as described above, has a frame transmitted from a base station to a modem card of a mobile terminal or a notebook computer employing Mobile WiMax technology, and estimates the amount of power required by the modem. Provided are an apparatus and a method for supplying.

Accordingly, an object of the present invention is to provide an apparatus and method for supplying power for a modem workload of a modem card of a mobile terminal or a notebook computer employing Mobile WiMax.

An apparatus according to an embodiment of the present invention is a device for controlling power in a mobile terminal, comprising: a receiving unit for receiving data from a base station, a modem for outputting data amount information on the received data, and the output data amount A workload predictor for predicting a workload required to process the received data based on the information, and determining a required amount of power based on the information about the estimated workload, and determining a voltage corresponding to the determined amount of power. A dynamic voltage frequency scaling (DVFS) driver instructing to control the voltage of the modem by a value, and a controller that controls the voltage of the modem according to the instruction of the DVFS driver.

According to an embodiment of the present invention, in a method for controlling power in a mobile terminal, a workload of a modem required to process the received data based on data amount information about data received from a base station And a step of determining a required amount of power based on the information on the estimated amount of work, and controlling a voltage of the modem with a voltage value corresponding to the determined amount of power.

The present invention is characterized by predicting the power consumption by analyzing the frame transmitted from the base station. In the present invention, when the mobile terminal operates, it predicts a task to be performed to lower the voltage and frequency when the workload is small, and raises the voltage and frequency when the workload is large. This approach has the advantage of reducing power consumption without affecting the performance of doing the same.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention.

The present invention provides an apparatus and method for reducing power consumption by analyzing data of a frame at a terminal or a base station to control driving of the modem.

1 is a block diagram of an apparatus for controlling power in a modem according to an exemplary embodiment of the present invention.

The transceiver 170 receives a frame received through the antenna ANT and converts the band down, and then transmits it to the modem or performs a band up conversion on the frame received from the modem and then transmits the band to the base station through the antenna. The modem 110 performs demodulation after digitally converting the received data, and simultaneously transmits the amount of information to be demodulated or the corresponding information to the workload meter 120. The workload meter 120 then predicts the workload to be performed in the modem 110 and provides the result to the DVFS driver 150. In the case of the downlink in the WiMax system, for example, the prediction of the operation amount is provided by scheduling a frame in units of 5ms in the WiMax system, and the scheduling information is stored and transmitted in the MAP. Therefore, you can use the information in the MAP to estimate how much the modem should handle.

In addition, the workload meter 120 tracks the operation of the modem 110 and its operation state, and provides the result to the DVFS driver 150. Taking the WiMax system as an example, the location information of each information element (hereinafter referred to as IE) in downlink can be confirmed from the information of the salping MAP, and since each IE includes a CRC, the location of the data burst The operation state of the modem is checked according to the information and the CRC result, and the result is provided to the DVFS driver 150.

The clock controller 140 provides a clock to a modem clock used in the modem 110 or a CPU inside the WiMax modem, and the modem 110 demodulates information such as data burst, MAP, and preamble, and modulates a signal to be transmitted. Perform the action.

Using the above information, the DVFS driver 150 calculates the power required by the modem 110 or the entire modem hardware 100, and provides a voltage raising command to the power controller 160 based on the calculated value. do. The power controller 160 then provides power by raising or lowering the voltage to the modem 110 or the modem hardware 100 using the information received from the DVFS driver 150. 2 is a structural diagram of data of a frame transmitted from a base station according to an exemplary embodiment of the present invention.

The frame transmitted and received from the base station may be illustrated as an Orthogonal Frequency Division Multiple Access (OFDMA) symbol period on the horizontal axis and a subchannel period on the vertical axis. The section of the horizontal axis is composed of symbols and is shown in k, k + 1, k + 2 format in FIG. The vertical axis is divided into subchannels and is illustrated in the form of s, s + 1, and s + 2 in FIG. 2. It is divided into a downlink (hereinafter referred to as "DL") 200 and an uplink (hereinafter referred to as "UL") 210 based on the horizontal axis.

Looking at the structure of the downlink 200, a preamble used for initial synchronization, cell search, frequency offset, and channel estimation is located in k symbols, and DL-MAP and FCH (Frame Control Header) are used in k + 1 symbols. ) Exists. The DL-MAP contains the location information of the DL-burst in the frame. If an error occurs by performing a CRC check on the DL-burst # 1 located at the k + 3 symbol, the DL-burst # 2, DL- It is determined that there is an error in burst # 3, DL-burst # 4, DL-burst # 5, and DL-burst # 6, and it is converted to idle time without any work up to k + 15 symbols. If an error does not occur in the DL-burst # 1, a CID (Connection ID) value is checked to determine whether it is a unicast or a broadcast. In the DL-burst # 2, the DL-burst # 6 is Perform the instructions. Transmit / receive transition gap (TGT) and receive / transmit transition gap (RTG) are inserted between the downlink 200 and the uplink 210 at the middle and the end of the frame.

Looking at the structure of the uplink 210, UL-burst # 1, UL-burst # 2, UL-burst # 3, UL-burst # 4, UL-burst # 5 from k + 17 symbols to k + 26 symbols Is located, the location is identified by checking the location information of the UL-MAP included in the DL-burst # 1. If the UL-MAP is present in the DL-burst # 1, the existence of a unicast CID is confirmed, and if there is a control region, the data of the DL-burst # 5 in the UL-burst # 2 To demodulate it. If the UL-MAP is not present in the UL-burst # 1, it is converted to an idle time.

3 is a detailed structural diagram of a map in frame data according to an exemplary embodiment of the present invention.

In FIG. 2, the DL-MAP containing the information of the DL-burst and the UL-MAP containing the information of the UL-burst are mentioned. The structure of the DL-MAP and UL-MAP will be described below.

The DL-MAP and the UL-MAP are divided into TYPE = 2 and TYPE = 3, and are classified into DL-MAP and UL-MAP by types included in a GMH (Generic MAC header). The TYPE = 2 includes DL-MAP Information Elements (DL-MAPs) having locations of DL-bursts and a cyclic redundancy check (CRC) for checking errors of the DL-MAP. The TYPE = 3 includes UL-MAP Information Elements (IEs) having positions of UL-bursts and a cyclic redundancy check (CRC) for checking an error of the UL-MAP.

4 is a mapping structure diagram of frame data according to an embodiment of the present invention.

In FIG. 3, a detailed structural diagram of the map in the frame data is shown. The DL-MAP and the UL-MAP of the map are mapped with DL-burst and UL-burst, that is, DL-MAP IE and DL. -burst is shown following.

The first DL-MAP IE has a Connection ID (hereinafter referred to as CID) indicating location information of DL-burst # 1, and the CID is composed of 16 bits. The second DL-MAP IE has location information of DL-burst # 2, and is like finding a location of the DL-burst # 1. Seems like finding the third and fourth DL-burst.

The UL-MAP IEs also include the location information of the UL-burst in order from the first.

5 is a flowchart of downlink in a frame according to an embodiment of the present invention.

The workload of the mobile terminal varies according to the characteristics of the channel and is not uniform. Accordingly, in order to predict the state of the workload, the transceiver 170 receives a frame from the base station and converts the workload of the frame into digital data in step 500. The converted digital data is demodulated in the modem 110, transmitted to the workload predictor 120, and transmitted to the DVFS driver 150.

In step 510, the workload measurer 120 checks whether there is a CRC error in the DL-MAP, and proceeds to step 550 if the error exists, and proceeds to step 520 if the error does not exist.

In step 520, the workload measurer 120 determines that the first bit of the CID (Most Significant Bit), that is, the CID prefix is 1, is either broadcast or multicast to step 550. If the prefix of the CID is 0, it is determined as unicast and the process proceeds to step 530.

In step 530, the workload measurer 120 performs a CRC check on DL-bursts ranging from DL-burst # 1 to DL-burst # 6 and proceeds to step 550 if there is an error. Proceed to step 540.

Since the DVFS driver 150 performs the operation indicated by the DL-burst # 6 from the DL-burst # 1 in step 540, it increases the clock and voltage until the next frame is received to the modem 110. After supplying, the process proceeds to step 560.

In step 550, the DVFS driver 150 reduces and supplies a clock and voltage to the modem 110 so that the modem 110 is converted to an idle time, and then proceeds to step 560. .

In step 560, the DVFS driver 150 processes the next frame.

6 is a flowchart of an uplink in a frame according to an embodiment of the present invention.

In step 600, the receiving unit 170 receives the frame from the base station and converts the digital data to know the workload of the frame. The converted digital data is demodulated in the modem 110 and transmitted to the workload meter 120 and transmitted to the DVFS driver 150.

In step 610, the DVFS driver 150 checks whether the location information of the UL-MAP exists in the DL-burst # 1, and proceeds to step 620 if the location information exists, and proceeds to step 650 if it does not exist.

In step 620, the DVFS driver 150 checks whether a unicast CID exists in the UL-MAP, and if the unicast CID exists, proceeds to step 630; otherwise, proceeds to step 650.

In step 630, the DVFS driver 150 checks whether there is a control region indicating work in each UL-burst from UL-burst # 1 to UL-burst # 5, and proceeds to step 640 if the control region exists. If the control area does not exist, the process proceeds to step 650.

Since the DVFS driver 150 performs the operation indicated by the UL-burst # 5 from the UL-burst # 1 in step 640, the clock and voltage are transmitted to each UL-burst until the next frame is received. After increasing to fit the modem 110, and proceeds to step 660.

In step 650, the DVFS driver 150 reduces and supplies a clock and voltage to the modem 110 so that the modem 110 is converted to an idle time, and then proceeds to step 660.

In step 660, the DVFS driver 150 processes the next frame.

1 is a block diagram of an apparatus for controlling a voltage and a clock in a modem according to a preferred embodiment of the present invention.

2 is a structural diagram of data of a frame transmitted from a base station according to an exemplary embodiment of the present invention.

3 is a detailed structural diagram of a map in frame data according to a preferred embodiment of the present invention.

4 is a mapping structure diagram of frame data according to an embodiment of the present invention.

5 is a flowchart of a downlink in a frame according to an embodiment of the present invention.

6 is a flowchart of an uplink in a frame according to an embodiment of the present invention.

Claims (6)

An apparatus for controlling power in a mobile terminal, Comprising: a receiver for receiving data from a base station; A modem for outputting data amount information on the received data; A workload predictor for predicting a workload required to process the received data based on the output data amount information; Dynamic Voltage Frequency Scaling (DVFS) driver which determines the amount of power required based on the information about the estimated workload and instructs to control the voltage of the modem to a voltage value corresponding to the determined amount of power. Wow, And a controller for controlling the voltage of the modem according to the instruction of the DVFS driver. The method of claim 1, wherein the DVFS driver, When a downlink map (MAP) is received, the voltage of the modem is increased or decreased depending on whether there is an error in the downlink burst (burst) included in the downlink map controller. The method of claim 2, wherein the DVFS driver, If there is no error in the downlink burst, it is determined whether the downlink burst includes location information of an uplink map, and the downlink burst includes location information of the uplink map. And if the control region is included in the uplink map, increasing or decreasing the voltage of the modem. In the method for controlling power in a mobile terminal, Estimating a workload of a modem required to process the received data based on data amount information about data received from a base station; Determining a required amount of power based on the information on the estimated amount of work; And controlling the voltage of the modem to a voltage value corresponding to the determined amount of power. 5. The method of claim 4, If a downlink map (MAP) is received, further comprising the step of increasing or decreasing the voltage of the modem according to whether there is an error in the downlink burst (burst) included in the downlink map Power control method. The method of claim 5, If there is no error in the downlink burst, it is determined whether the downlink burst includes location information of an uplink map, and the downlink burst includes location information of the uplink map. And if the control region is included in the uplink map, increasing or decreasing the voltage of the modem.

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