WO2015021784A1

WO2015021784A1 - Method and terminal for adjusting wifi transmission power

Info

Publication number: WO2015021784A1
Application number: PCT/CN2014/075455
Authority: WO
Inventors: 白剑
Original assignee: 惠州Tcl移动通信有限公司
Priority date: 2013-08-12
Filing date: 2014-04-16
Publication date: 2015-02-19
Also published as: CN103415066A; CN103415066B

Abstract

Disclosed are a method and terminal for adjusting Wireless Fidelity (WiFi) transmission power. The method comprises the following steps: A) upon the activation of a WiFi module, a terminal detects the current WiFi standard and modulation mode, and controls the WiFi module for an interval of a first preset time to obtain a received signal strength indicator (RSSI) value (S100) of the current WiFi hotspot; B) calculating the matching WiFi transmission power according to the current WiFi standard, modulation mode and RSSI value（S200）; C) the WiFi module transmits according to the WiFi transmission power (S300). The method of calculating the current more suitable WiFi transmission power according to the current WiFi standard, modulation mode and RSSI value in an embodiment of the present invention achieves the result of dynamically adjusting the WiFi transmission power according to the RSSI value, thus saving WiFi power consumption and increasing the battery life of the terminal.

Description

Method and terminal for adjusting WIFI transmission power

The present invention relates to the field of communications technologies, and in particular, to a WIFI transmit power adjustment method and terminal. Background technique

At present, most terminals support WIFI (Wireless Fidelity) technology. The WIFI module can connect the terminal to the network through radio waves within the effective range, without wiring or wiring conditions. Therefore, this WIFI access method It is favored by more and more users. However, the WIFI module consumes a lot of power, and if it is used more frequently, it will accelerate the loss of battery power.

In the existing terminal, the WIFI module does not introduce a power control mechanism, that is, the WIFI module of the existing terminal transmits data with a fixed transmission power (a value between 12 dBm and 20 dBm). In general, if the distance between the terminal and the wireless hotspot is relatively long, a large transmission power is required; when the distance is relatively close, a small transmission power is required. The transmit power based on the existing terminal WIFI is fixed, and there is no relevant mechanism to adjust the size of the transmit power, and the power control is automatically performed. If the distance between the terminal and the wireless hotspot is very close, the transmission power at this time is relatively large, which is equivalent to wasting some power and increasing power consumption. If the distance between the terminal and the wireless hotspot is very long, the transmission power at this time is relatively small, and the signal may be unstable, resulting in data transmission being more convincing or even transmission failure. Summary of the invention

In view of the above deficiencies of the prior art, it is an object of the present invention to provide a

The method and terminal for adjusting the WIFI transmit power are used to solve the problem that the existing terminal cannot adjust the WIFI transmit power, resulting in increased power consumption and large power consumption.

In order to achieve the above object, the present invention draws the following technical solutions: A method for adjusting WIFI transmit power, which includes:

A. When the WIFI module is enabled, the terminal detects the current WIFI system and the modulation mode, and controls the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time;

B. Calculate the matching WIFI transmit power according to the current WIFI standard, modulation mode and RSSI value;

The C and WIFI modules transmit according to the WIFI transmit power.

In the method for adjusting the WIFI transmission power, in the step B, the method for calculating the current WIFI transmission power includes a table lookup method and a calculation method.

In the method for adjusting the WIFI transmit power, the look-up table method includes: querying, according to the RSSI value, a corresponding WIFI transmit power in a transmit power correspondence table, and outputting the WIFI transmit power to the WIFI module.

In the method for adjusting the WIFI transmit power, before the step A, the method further includes storing the transmit power correspondence table and storing the data in a non-volatile memory; the transmit power correspondence table includes a WIFI system and a modulation mode. Related data, the range of values of the RSSI value and the range of values of the corresponding WIFI transmit power.

In the method for adjusting the WIFI transmit power, the calculation method includes: B l, the terminal communicates with the WIFI hotspot to obtain the current reported transmission power of the WIFI hotspot, and queries the demodulation threshold of the WIFI hotspot;

B2, calculating a spatial loss according to the RSSI value and the reported transmission power;

B3. Calculate the current WIFI transmit power according to the demodulation threshold and the spatial loss. In the method for adjusting the WIFI transmission power, the calculation formula of the space loss is: Pathloss = Power _{AP report} - Power _AP ,

The WIFI emission power calculation formula is:

TXPowr = THR _demod + Pathloss where Pathloss is the space loss, ^Power A _P , _r , _rt is the current reported transmit power of the _WIFI hotspot, ^PmV ^P is _RS S i, T^^mcd is the demodulation threshold, TXP is hidden

WIFI transmit power.

In the method for adjusting the WIFI transmit power, after the step B3, the method further includes:

B4. Counting the packet loss rate in the second preset time;

B5. Determine whether the packet loss rate is greater than an adjustment threshold; increase the WIFI transmit power when the packet loss rate is greater than the adjustment threshold, and decrease the WIFI transmit power when the packet loss rate is less than the adjustment threshold.

In the method for adjusting the WIFI transmission power, in the step B5, the WIFI transmission power is increased or decreased according to the preset step size. A method for adjusting WIFI transmit power, wherein:

A. When the WIFI module is turned on, the terminal detects the current WIFI system and modulation mode. Controlling the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time;

B. Calculate the matched WIFI transmit power according to the current WIFI standard, modulation mode, and RSSI value; the method for calculating the current WIFI transmit power includes a lookup table method and a calculation method; the lookup table method includes: The RSSI value is used to query the corresponding WIFI transmit power in the transmit power correspondence table, and output the WIFI transmit power to the WIFI module; the calculation method includes:

B l. The terminal communicates with the WIFI hotspot to obtain the current reported transmit power of the WIFI hotspot, and queries the demodulation threshold of the WIFI hotspot;

B3. Calculating a current WIFI transmit power according to a demodulation threshold and a space loss;

The C and WIFI modules transmit according to the WIFI transmit power. The method for adjusting the WIFI transmit power, wherein before the table lookup, the transmit power correspondence table is set and stored in the non-volatile memory. The method for adjusting the WIFI transmit power, wherein, before the step A, further comprising storing the transmit power correspondence table; the transmit power correspondence table includes related data of a WIFI system and a modulation mode, and a value of the RSSI value The range and the range of WIFI transmit power corresponding to it.

The method for adjusting the WIFI transmission power, wherein the calculation formula of the space loss is: Pathloss = Power _{AP report} ― Power _AP ;

The wiFi transmit power is calculated as: TXPOwr = THR _demod + Pathloss Among them, Pathloss is the space loss, ^Pow£r A _P is the current reported transmit power of the _WIFI hotspot, ^ ^^ is the RSSI value, T^^fem^ is the demodulation threshold, and n/^vvr is the WIFI transmit power. The method for adjusting the WIFI transmit power, wherein, after the step B3, the method further includes:

B4. Counting the packet loss rate in the second preset time;

The method for adjusting the WIFI transmit power, wherein, in the step B5, the WIFI transmit power is increased or decreased according to a preset step size.

A terminal for implementing the method for adjusting a WIFI transmit power, comprising:

The CPU is used to detect the current WIFI system and the modulation mode when the WIFI module is enabled, and control the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time; on the other hand, the current WIFI is used according to the current WIFI. The system, modulation mode and RSSI value obtain the current WIFI transmit power;

The WIFI module is configured to detect the RSSI value of the current WIFI hotspot and transmit it to the CPU; on the other hand, to transmit according to the WIFI transmit power;

The first timer is configured to set a first preset time.

The terminal further includes:

a non-volatile memory, configured to store a transmit power correspondence table;

The second timer is configured to set a second preset time. Compared with the prior art, the WIFI transmit power adjustment method and the terminal provided by the present invention detect the current WIFI system and the modulation mode when the WIFI module is turned on, and acquire the RSSI value of the WIFI hotspot every first preset time. According to the current WIFI system, modulation mode and RSSI value, the current more suitable WIFI transmit power is calculated, and the control WIFI module transmits according to the WIFI transmit power, thereby achieving the effect of dynamically adjusting the WIFI transmit power according to the RSSI value, thereby saving The power consumption of WIFI improves the terminal's battery life.

DRAWINGS

1 is a flow chart of a method for adjusting WIFI transmit power according to the present invention.

2 is a structural block diagram of a terminal of the present invention. detailed description

The invention provides a method and a terminal for adjusting the WIFI transmit power, and can calculate the most suitable WIFI transmit power according to the currently used WIFI standard, modulation mode and RSSI (Received Signal Strength Indication) value, and then control The WIFI module uses the WIFI transmit power to transmit to save power.

The present invention will be further described in detail below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The terminal of the present invention is a smartphone, a tablet, a notebook, and the like. Please refer to the picture

1, which is a flowchart of a method for adjusting WIFI transmission power of the present invention. As shown in FIG. 1, the method for adjusting the WIFI transmit power includes:

S100: When the WIFI module is enabled, the terminal detects the current WIFI system and the modulation mode, and controls the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time.

The WIFI system indicates the WIFI standard currently used by the terminal, such as 802.11a (54Mbps), 802.11b (11Mbps), or 802.11g (54Mbps), which is the wireless network protocol. The modulation mode corresponds to the WIFI system, and the data is basically fixed. The terminal can detect the specific data of the modulation mode and the WIFI system, which is a prior art, and the present invention does not limit this.

S200 calculates the matching WIFI transmit power according to the current WIFI system, modulation mode and RSSI value.

The S300 and the WIFI module transmit according to the WIFI transmission power.

In step S200, the method of calculating the current WIFI transmission power includes a look-up table method and a calculation method. Take the smart phone as an example to illustrate how to use the look-up table method and calculation method to obtain the most suitable WIFI transmit power.

First, look up the table method:

The look-up table method includes: querying, according to the RSSI value, a corresponding WIFI transmit power in a transmit power correspondence table, and outputting the WIFI transmit power to a WIFI module.

Before the table lookup, the transmit power correspondence table needs to be set and stored in the non-volatile memory; the transmit power correspondence table includes related data of the WIFI system and the modulation mode. The range of values of the RSSI value and the range of values of the corresponding WIFI transmit power. The setting of the transmission power correspondence table is as shown in Table 1 below.

Table 1

The RSSI in Table 1 indicates the signal strength of the WIFI hotspot received by the terminal, and the terminal controls the WIFI module to detect the RSSI value once every first preset time (such as 3s), which is changed. The WIFI system and modulation method are related to the type of WIFI module currently used. The type of WIFI module is determined by the manufacturer, which determines the parameters of the WIFI system and modulation mode. The RSSI value corresponds to the WIFI system and the modulation method, and the corresponding manner is as shown in Tables 1 and 2 above, which is a prior art. The invention mainly sets the correspondence between the RSSI value and the transmission power.

When the RSSI value is greater than or equal to -80 dBm, the transmit power is also greater than or equal to 21 dBm; when the RSSI value is less than -80 dBm and greater than or equal to -70 dBm, the transmit power is Any value from 19dBm to 21dBm, preferably equal to 19dBm; when the RSSI value is less than -70 dBm and greater than or equal to -65dBm, the transmit power is any value from 17dBm to 19dBm, preferably equal to 17dBm; when the RSSI value is less than - When the 65 dBm is greater than or equal to -60 dBm, the transmit power is any value from 15 dBm to 17 dBm, preferably equal to 15 dBm; when the RSSI value is less than -60 dBm and greater than -55 dBm, the transmit power is any value from 12 dBm to 15 dBm; When the RSSI value is less than or equal to -55 dBm and greater than or equal to -50 dBm, the transmit power is any value from 8 dBm to 12 dBm, preferably equal to 8 dBm; when the RSSI value is less than -50 dBm and greater than or equal to -48 dBm, the transmit power is 5 dBm. Any value in ~8dBm, preferably equal to 5dBm; when the RSSI value is less than -48 dBm and greater than or equal to -45dBm, the transmit power is any value from 0dBm to 5dBm, preferably equal to OdBm; when the RSSI value is less than -45 When dBm is greater than or equal to -40 dBm, the transmission power is any value from -5 dBm to 0 dBm, preferably equal to -5 dBm.

It can be seen from the above Table 1 that as long as the RSSI value is known, the corresponding WIFI transmission power can be queried, and the WIFI module can transmit according to the queried WIFI transmission power. It should be understood that the above table only lists the correspondence between the commonly used RSSI value and the transmission power, and the remaining correspondences are supplemented by the manufacturer during the specific implementation. The above table may have other formats, which are not limited in the present invention.

Second, the calculation method:

The calculation method includes:

Step 201: The terminal communicates with the WIFI hotspot to obtain the current reported transmit power of the WIFI hotspot, and queries the demodulation threshold of the WIFI hotspot;

Step 202: Calculate a spatial loss according to the RSSI value and the reported transmit power. Step 203: Calculate a current WIFI transmit power according to a demodulation threshold and a spatial loss.

The calculation formula of the space loss is: P thloss = Power _{AP report} - Power _AP ; The calculation formula of the wiFi transmission power is: = ^THR _d emod + Pathloss where Pathloss is the space loss and ^{Pow £r} A _P is the current report of the _WIFI hotspot. Transmit power, ^ ^^ is the RSSI value, T^^fem^ is the demodulation threshold, and n/^vvr is the WIFI transmit power.

Above / 3⁄4 rw. The values of _rt and THR _{dem d} are constant. They are related to the modulation system and demodulation mode. You can query the data sheet of the WIFI module. The value of ^PmVi ^p is obtained by the terminal controlling the WIFI module every first preset time.

In order to demodulate the signal transmitted by the terminal, the signal received by the receiving end (such as the WIFI hotspot) should not be lower than the demodulation threshold to correctly demodulate the received signal; at the same time, the signal has a certain loss in the space transmission process. Therefore, the minimum value of WIFI transmit power should be the sum of the space loss and the demodulation threshold. In this way, based on the current RSSI value, the unique WIFI transmit power is calculated, which improves the efficiency of the transmission and saves power consumption.

Based on the interference in the actual transmission process, the final transmission rate is different under the same received signal strength. Therefore, the foregoing calculation process may be completed in combination with the packet loss rate, and after the step 203, the method further includes:

Step 204: Count a packet loss rate in a second preset time period;

Step 205: Determine whether the packet loss rate is greater than an adjustment threshold; increase the WIFI transmit power when the packet loss rate is greater than the adjustment threshold, and decrease the WIFI when the packet loss rate is less than the adjustment threshold. Transmit power.

In the WIFI standard transmission/feedback mechanism, each time a terminal transmits a set of data (each group of data is a data packet), the WIFI hotspot will decode. If the WIFI hotspot successfully receives the data, it will return ACK (Acknowledgement, confirmation character). If the data reception fails, a NACK (Negative Acknowledgement) is returned. Data reception failure is also called data loss because the data is not transmitted to the WIFI hotspot or only part of the data is transmitted. By calculating the ratio of the number of lost packets to the transmitted packet, that is, the packet loss rate, it is possible to more accurately determine whether the current WIFI transmission power is appropriate.

The terminal counts the probability of occurrence of all NACKs in the second preset time (such as 3s), that is, the packet loss rate. The calculation formula is: NACK ^=NACK number / (number of ACK + number of NACK), where NACK rate is the packet loss rate. If the NACK rate is greater than the first preset adjustment threshold (such as 0.1), indicating that the data loss is more, the WIFI transmission power needs to be increased; if the NACK rate is less than the first preset adjustment threshold (such as 0), the WIFI transmission power needs to be reduced; If the NACK rate is between the first preset adjustment threshold and the second preset adjustment threshold, the WIFI transmission power may remain unchanged. When the WIFI transmit power is increased or decreased, the preset step size is increased or decreased. For example, the step size of the ldB can be increased or decreased every time. The WIFI transmission power thus obtained is based on the actual data reception condition, and can continuously and dynamically adjust the WIFI transmission power in real time, further improving the calculation accuracy and allowing the terminal to be in an optimal power consumption state.

It should be noted that after the RSSI value and its corresponding WIFI transmit power are calculated by the calculation method, the RSSI value and the corresponding WIFI transmit power can be written into the transmit power correspondence table, so as to improve the transmit power correspondence table, Table can get WIFI launch Power, which shortens the calculation time and speeds up the transmission.

Based on the foregoing method for adjusting the transmit power of the WIFI, the embodiment of the present invention further provides a terminal. Referring to FIG. 2, the CPU 10 includes a CPU 10, a WIFI module 20, and a first timer 30. The CPU 10 is connected to the WIFI module 20. And the first timer 30. The first timer 30 is used to set the first preset time. On the one hand, the CPU 10 detects the current WIFI system and the modulation mode when the WIFI module 20 is turned on, and controls the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time; on the other hand, according to the current WIFI standard. The modulation mode and the RSSI value calculate the matching WIFI transmit power. The WIFI module 20 is configured to detect the RSSI value of the current WIFI hotspot every first preset time according to the control of the CPU and transmit it to the CPU; and on the other hand, to transmit according to the calculated WIFI transmit power.

The terminal further includes a nonvolatile memory 40 for storing a transmission power correspondence table, and a second timer 50 for setting a second preset time, the nonvolatile memory 40, the second timer 50 Both are connected to the CPU 10.

The CPU 10 can use a WIFI baseband chip. The non-volatile memory 40 can utilize the memory space in the WIFI baseband chip.

In summary, the present invention detects the current WIFI system and modulation mode when the WIFI module is turned on, and acquires the RSSI value of the WIFI hotspot every first preset time, according to the current WIFI standard, modulation mode, and RSSI value. The WIFI transmit power is obtained by using the look-up table method or the calculation method, and the WIFI module is controlled to transmit according to the WIFI transmit power, thereby achieving the effect of dynamically adjusting the WIFI transmit power according to the RSSI value, improving the transmission efficiency and saving power consumption. The terminal is in the best power consumption state, and the continuation of the terminal is improved. Flight time.

It is to be understood that those skilled in the art can make equivalent substitutions or changes to the inventions and the inventions of the invention.

Claims

claims

1. A method for adjusting WIFI transmission power, which is characterized by including:

A. When the WIFI module is turned on, the terminal detects the current WIFI standard and modulation method, and controls the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time;

B. Calculate the matching WIFI transmission power based on the current WIFI standard, modulation method and RSSI value;

C. The WIFI module transmits according to the WIFI transmission power.

2. The method for adjusting WIFI transmission power according to claim 1, characterized in that, in step B, the method for calculating the current WIFI transmission power includes a table lookup method and a calculation method.

3. The method for adjusting WIFI transmission power according to claim 2, wherein the table lookup method includes: querying the corresponding WIFI transmission power in the transmission power corresponding table according to the RSSI value, and adjusting the WIFI transmission power. The transmit power is output to the WIFI module.

4. The method for adjusting WIFI transmission power according to claim 3, characterized in that, before step A, it further includes storing the transmission power correspondence table; the transmission power correspondence table includes WIFI standard and modulation method. Relevant data, the range of RSSI values and the range of corresponding WIFI transmission power.

5. The method for adjusting WIFI transmission power according to claim 2, characterized in that the calculation method includes:

Bl. The terminal communicates with the WIFI hotspot to obtain the current reported transmit power of the WIFI hotspot. Query the demodulation threshold of the WIFI hotspot;

B2. Calculate space loss based on RSSI value and reported transmit power;

B3. Calculate the current WIFI transmit power based on the demodulation threshold and space loss.

6. The method for adjusting WIFI transmission power according to claim 5, characterized in that the calculation formula of the spatial loss is: P thloss = Power _{AP report} - Power _AP ;

The WiFi transmit power calculation formula is: = ^THR _d emod + Pathloss where, Pathloss is the space loss, ^Pow£r A _P is the current reported transmit power of _{the WIFI} hotspot, ^ ^^ is the RSSI value, and T^^fem^ is the demodulation threshold. , n/^vvr is the WIFI transmission power.

7. The method for adjusting WIFI transmission power according to claim 6, characterized in that, after step B3, it further includes:

B4. Count the packet loss rate within the second preset time;

B5. Determine whether the packet loss rate is greater than the adjustment threshold; when the packet loss rate is greater than the adjustment threshold, increase the WIFI transmission power, and when the packet loss rate is less than the adjustment threshold, reduce the WIFI transmission power.

8. The method for adjusting WIFI transmission power according to claim 7, characterized in that, in step B5, the WIFI transmission power is increased or decreased according to a preset step size.

9. A method for adjusting WIFI transmission power, characterized by including:

A. When the WIFI module is turned on, the terminal detects the current WIFI standard and modulation method, and controls the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time; B. Calculate the matching WIFI transmission power based on the current WIFI format, modulation method and RSSI value; the method for calculating the current WIFI transmission power includes a table lookup method and a calculation method; the table lookup method includes: according to the The RSSI value queries the corresponding WIFI transmission power in the transmission power corresponding table, and outputs the WIFI transmission power to the WIFI module; the calculation method includes:

Bl. The terminal communicates with the WIFI hotspot to obtain the current reported transmit power of the WIFI hotspot, and queries the demodulation threshold of the WIFI hotspot;

B2. Calculate space loss based on RSSI value and reported transmit power;

B3. Calculate the current WIFI transmit power based on the demodulation threshold and space loss;

C. The WIFI module transmits according to the WIFI transmission power.

10. The WIFI transmission power adjustment method according to claim 9, characterized in that, before looking up the table, a transmission power corresponding table is first set and stored in a non-volatile memory.

11. The method for adjusting WIFI transmission power according to claim 10, characterized in that, before step A, further comprising storing the transmission power correspondence table; the transmission power correspondence table includes WIFI standard and modulation method. Relevant data, the range of RSSI values and the range of corresponding WIFI transmission power.

12. The method for adjusting WIFI transmission power according to claim 9, characterized in that the calculation formula of the spatial loss is: P thloss = Power _{AP report} - Power _AP ; The formula for calculating WIFI transmit power is: = ^THR _d emod + Pathloss where Pathloss is the space loss, ^Pow£r A _P is the current reported transmit power of _{the WIFI} hotspot, ^ ^^ is the RSSI value, and T^^fem^ is the demodulation threshold. , n/^vvr is the WIFI transmission power.

13. The method for adjusting WIFI transmission power according to claim 12, characterized in that, after step B3, it further includes:

B4. Count the packet loss rate within the second preset time;

14. The method for adjusting WIFI transmission power according to claim 13, characterized in that, in step B5, the WIFI transmission power is increased or decreased according to a preset step size.

15. A terminal used to implement the WIFI transmission power adjustment method described in any one of claims 1-14, characterized in that it includes:

The CPU, on the one hand, is used to detect the current WIFI standard and modulation method when the WIFI module is turned on, and control the WIFI module to obtain the RSSI value of the current WIFI hotspot every first preset time; on the other hand, it is used to detect the current WIFI The standard, modulation method and RSSI value are used to obtain the current WIFI transmission power;

The WIFI module, on the one hand, is used to detect the RSSI value of the current WIFI hotspot and transmit it to the CPU; on the other hand, it is used to transmit according to the WIFI transmission power;

The first timer is used to set the first preset time.

16. The terminal according to claim 15, further comprising: a non-volatile memory for storing a transmission power corresponding table;

The second timer is used to set the second preset time.