KR102222003B1 - High quality phone-calling system and apparatus using Wi-Fi mode changing - Google Patents

Abstract

The present invention relates to a high-quality call method and device, and more specifically, in a call method and device using a wireless LAN, after calculating a call quality index according to an operation mode of a current wireless LAN at a time when a call is initiated, The present invention relates to a high-quality call method and apparatus using a wireless LAN operation mode change capable of improving call quality by changing to an appropriate operation mode when the reference value of is not met.
The present invention provides a step of connecting a terminal to a wireless LAN (WiFi) access point; Initiating a call at the terminal; Call quality determination step of determining the level of meeting call quality by calculating a call quality index in case of conducting a call using the WLAN operation mode at the time of call initiation according to a predetermined standard, and comparing it with a preset call quality standard value. ; And an operation mode determining step of determining whether or not to change a wireless LAN operation mode and a content of the change in the terminal by reflecting the call quality satisfaction level, wherein the wireless LAN operation mode includes a wireless LAN protocol. It has the effect of initiating a call method using

Description

[High quality phone-calling system and apparatus using Wi-Fi mode changing}

The present invention relates to a high-quality call method and device, and more specifically, in a call method and device using a wireless LAN, a call quality index according to an operation mode of a current wireless LAN is calculated at a time when a call is initiated, and then a predetermined call quality index is calculated. The present invention relates to a high-quality call method and apparatus using a wireless LAN operation mode change capable of improving call quality by changing to an appropriate operation mode when the reference value of is not met.

With the development of wireless communication services, voice and video calls such as VoIP using data networks are rapidly spreading. In particular, in the case of providing a voice or video call using a data network, due to the characteristic of real-time two-way communication between both callers, unlike the case of general data transmission, the sensitivity to delay and jitter is large, Real-time quality assurance of the product should be considered more importantly.

In addition, despite the proliferation of 3G/4G wireless communication networks, wireless LAN (WiFi) still occupies an important part as a wireless data network. In particular, due to high wireless communication data rates, there are still many cases in which a large number of users prefer to make a voice or video call using a wireless LAN (WiFi). 1 illustrates a configuration diagram of a communication system using a conventional wireless LAN according to the prior art.

However, in a wireless LAN that mainly uses the 2.4GHz/5GHz ISM (Industrial, Scientific, Medical) band, signal distortion may occur due to the mobile environment, fading, and multi-path signals. Due to the characteristics of the ISM band, which is an open common channel, it can be freely used by various services, and thus signal attenuation factors such as signal interference by other services using the same frequency band may appear. Accordingly, a delay or loss of voice/video call data or distortion of a signal may cause a decrease in call quality due to noise such as delay or jitter of the voice/video during a call. 2 is a diagram illustrating the occurrence of channel interference in a wireless LAN (2.4GHz). As can be seen in FIG. 2, 13 channels are defined in the frequency band of the 2.4GHz wireless LAN (though it may vary depending on the country). However, even if one user is using channel 1, another user can use channel 2, so that a certain portion of the frequency band overlaps and channel interference may occur. In addition, since the same frequency band can be freely used by various services due to the characteristics of the ISM band as well as interference by the same wireless LAN signal, the possibility of inter-signal interference exists.

Accordingly, even if an external interference signal exists, there is a continuing demand for a call method and apparatus capable of performing high-quality voice/video calls by suppressing noise such as delay or jitter of voice/video using a wireless LAN (WiFi) as much as possible. However, an appropriate solution to this has not yet been presented.

The present invention was devised to solve the problems of the prior art as described above, and even if an external interference signal exists, a high-quality voice/video call can be performed by suppressing noise such as delay or jitter of voice/video using a wireless LAN as much as possible. It is an object of the present invention to provide a call method and apparatus that can be used.

A call method using a wireless LAN according to an aspect of the present invention for solving the above problem comprises the steps of: a terminal accessing a wireless LAN (WiFi) access point; Initiating a call at the terminal; Call quality determination step of determining the level of satisfaction of the call quality by calculating the call quality index in the case of conducting a call using the WLAN operation mode at the time of call initiation according to a predetermined standard, and comparing it with a preset call quality standard value. ; And an operation mode determining step of determining whether or not to change a wireless LAN operation mode and a content of the change in the terminal by reflecting the call quality satisfaction level, wherein the wireless LAN operation mode includes a wireless LAN protocol.

Here, in the call quality determination step, the call quality index may be calculated using one or more of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in the WLAN operation mode at the time of initiating the call. have.

In addition, in the operation mode determination step, it may be determined to change to a wireless LAN protocol having a maximum data rate lower than a maximum data rate in the wireless LAN protocol at the time of initiating a call.

In addition, in the operation mode determination step, it may be determined to change the protocol of the wireless LAN operation mode to be changed to 802.11b without considering other conditions.

In addition, in the operation mode determination step, after calculating the sum of the data rate in the wireless LAN used by the terminal at the time of the call start and the data rate additionally generated by the call, , It is determined to change to the smallest data rate standard among the data rate standards having a data transmission rate greater than the sum in the WLAN protocol at the time of the call initiation, and in this case, in the WLAN operation mode, the WLAN data transmission rate ( datarate) may be further included.

In addition, a data rate value corresponding to data whose transmission is stopped due to the call may be subtracted from the data rate in the wireless LAN used by the terminal at the time of the call initiation.

In addition, in the operation mode determination step, a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) of each channel are used to determine to change to a channel that satisfies a predetermined reference value, and In this case, a wireless LAN channel may be further included in the wireless LAN operation mode.

In addition, when the call is terminated by the terminal, the step of returning to the wireless LAN operation mode at the time when the call is initiated or changing to the wireless LAN operation mode determined according to a predetermined criterion at the time when the call is ended may be further included.

A terminal having a call function using a wireless LAN according to another aspect of the present invention includes a wireless LAN communication unit for accessing a wireless LAN (WiFi) through an access point; A call unit that provides a call function with another terminal; A call quality determination unit that calculates the call quality index in the case of conducting a call using the WLAN operation mode at the time of call initiation according to a predetermined standard, and then compares it with a predetermined call quality standard value to determine the level of call quality satisfaction. ; And an operation mode determining unit configured to determine whether or not to change a wireless LAN operation mode and a content of the change in the terminal by reflecting the call quality satisfactory level, and the wireless LAN operation mode includes a wireless LAN protocol.

Here, the call quality determination unit may calculate a call quality index using one or more of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in the WLAN operation mode at the time of the call initiation. have.

In addition, the operation mode determiner may determine to change to a wireless LAN protocol having a maximum data rate lower than a maximum data rate in the wireless LAN protocol at the time of initiating a call.

In addition, the operation mode determination unit may determine to change the protocol of the wireless LAN operation mode to be changed to 802.11b without considering other conditions.

In addition, the operation mode determination unit calculates the sum of the data rate in the wireless LAN used by the terminal at the time of the call start and the data rate additionally generated by the call. , It is determined to change to the smallest data rate standard among the data rate standards having a data transmission rate greater than the sum in the WLAN protocol at the time of the call initiation, and in this case, in the WLAN operation mode, the WLAN data transmission rate ( datarate) may be further included.

In addition, a data rate value corresponding to data whose transmission is stopped due to the call may be subtracted from the data rate in the wireless LAN used by the terminal at the time of the call initiation.

In addition, in the operation mode determination unit, using at least one of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in each channel, it is determined to change to a channel that satisfies a predetermined reference value, and In this case, a wireless LAN channel may be further included in the wireless LAN operation mode.

In addition, when a call is terminated by the terminal, the wireless LAN operation mode may be returned to the wireless LAN operation mode at the time when the call is initiated, or the wireless LAN operation mode may be changed to the wireless LAN operation mode determined according to a predetermined criterion at the time of the call termination.

According to the present invention, in a call method and apparatus using a wireless LAN, if a call quality index is calculated at a time when a call is initiated and the call quality index is not met, the wireless LAN protocol, data rate, and It has the effect of disclosing a high-quality call method and apparatus using a change in an operation mode of a wireless LAN that can improve call quality by minimizing the influence of an external interference signal by changing one or more of the channels.

The accompanying drawings, which are included as part of the detailed description to aid in understanding of the present invention, provide embodiments for the present invention, and describe the technical idea of the present invention together with the detailed description.
1 is a block diagram of a communication system using a wireless LAN according to the prior art.
2 is an explanatory diagram of the occurrence of channel interference in a wireless LAN (2.4GHz) according to the prior art.
3 is a flowchart of a high-quality call method through a wireless LAN protocol change according to an embodiment of the present invention.
4 is a table for explaining an operation mode according to a wireless LAN standard.
5 is a flowchart of a high-quality call method by changing a wireless LAN protocol and a data rate according to an embodiment of the present invention.
6 is a flowchart of a high-quality call method through a wireless LAN protocol and channel change according to an embodiment of the present invention.
7 is a block diagram of a terminal having a call function using a wireless LAN according to an embodiment of the present invention.

The present invention may apply various transformations and may have various embodiments. Hereinafter, specific embodiments will be described in detail based on the accompanying drawings.

In describing the present invention, when it is determined that a detailed description of a related known technology may obscure the subject matter of the present invention, a detailed description thereof will be omitted.

Terms such as first and second may be used to describe various components, but the components are not limited by the terms, and the terms are only for the purpose of distinguishing one component from other components. Is used.

According to the present invention, when a voice/video call service is provided using a wireless LAN (WiFi) according to the prior art, signal interference with other devices using other channels of the wireless LAN may occur, and an ISM called an open public channel. Due to the characteristics of the band, signal attenuation factors such as signal interference by other services using the same frequency band may appear. Accordingly, delay or loss of audio/video call data or signal distortion may result in a delay in audio/video during a call. Focusing on the problem that call quality may deteriorate due to noise such as noise, jitter, etc., and if the call quality index at the time of starting the call is calculated and does not meet a predetermined standard value, the wireless LAN protocol and data rate ), a high-quality call method and apparatus using a change in an operation mode of a wireless LAN that can improve call quality by minimizing the influence of an external interference signal by changing one or more of the channels.

Hereinafter, exemplary embodiments of a high-quality call method and apparatus using a wireless LAN operation mode change according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, FIG. 3 shows a flow chart of a high-quality call method through a wireless LAN protocol change according to an embodiment of the present invention. As can be seen in Figure 3, the high-quality call method through a wireless LAN protocol change according to an embodiment of the present invention is a step of connecting a terminal to a wireless LAN (WiFi) access point (S310), a call from the terminal. In step S320 of the start of the call, the call quality index when the call is conducted using the wireless LAN protocol at the time of the call initiation is calculated according to a predetermined criterion, and then the call quality satisfactory level is determined by comparing it with a predetermined call quality reference value. Determining the call quality determination step (S330), the operation mode determination step (S340) of determining whether to change the wireless LAN protocol and details of the change in the terminal by reflecting the call quality satisfactory level (S340), the step of changing the wireless LAN protocol (S350) It may be configured to include a step (S360) of changing to a wireless LAN protocol determined according to a predetermined criterion at the end of the call.

In the following, a high-quality call method through a wireless LAN protocol change according to an embodiment of the present invention is divided into each step and examined in detail. First, in the step of connecting a terminal to a wireless LAN (WiFi) access point (S310), a predetermined terminal such as a VoIP phone, a smartphone, a tablet PC, and a laptop PC used by the user accesses the wireless LAN (WiFi). It connects to the access point and connects to the network. Accordingly, the user can make a voice/video call with another user connected to the network using an audio/video call application built in or installed and driven in the terminal. Since this step can be carried out without any particular difficulty according to the conventional technique, it will not be examined in detail here.

Next, look for the step (S320) in which the call is initiated in the terminal. Even before a call is initiated, a user can perform data communication in various ways, such as surfing the Internet using a terminal such as a smartphone, downloading a predetermined content, or uploading a predetermined file. However, when a call is initiated from the terminal, the operating environment of the terminal may vary greatly. For example, looking at a case where a user surfs the Internet, the user prefers to have a high data rate of the network in order to quickly load the Internet homepage and play the multimedia contents included in the homepage. In this case, a slight delay in data is not a big problem. Therefore, in this case, it would be desirable to set the operation mode of the wireless LAN to have a high data transmission rate.

However, circumstances may vary somewhat when a user makes a voice or video call using a wireless LAN. This is because, in the case of making a voice or video call, a data transmission rate higher than the required level does not have a significant effect on the call quality, so the data transmission rate is not a very important factor. For example, since voice calls only require a data rate of 23.85kbps based on AMR (Adaptive Multi-Rate) wideband, and wired calls require a data rate of 64kbps, the data rate of the wireless LAN is 54Mbps to several Gbps. It can be seen that even a very low data rate is sufficient compared to the one supported up to.

On the other hand, if there is a delay or loss of a call packet or a signal is distorted due to an interference signal that may be generated by an external device, a delay in voice/video may occur during a call, or a decrease in call quality due to noise such as jitter may occur. Therefore, it is more important to minimize the influence of external interference signals when making a voice or video call using a wireless LAN. In particular, the ISM band used by a wireless LAN (WiFi) can be freely used by a variety of services due to the nature of an open public channel, so it is more likely that signal interference by other services using the same frequency band will occur.

Accordingly, in the high-quality call method using the operation mode change of the wireless LAN according to the present invention, the normal wireless LAN setting is not used as it is, but the operation mode is changed to an operation mode capable of reducing external signal interference during a voice/video call. By doing so, it is possible to make high-quality calls using a wireless LAN.

Next, call quality in which a call quality index is calculated according to a predetermined criterion when a call is made using a wireless LAN protocol at the time of call initiation, and then compared with a preset call quality criterion to determine the level of call quality satisfaction. Look for the determination step (S330). When a call is initiated, the terminal calculates, according to a predetermined criterion, how much a call quality index will be obtained when a call is made using the current protocol. At this time, various methods may be used to calculate the call quality index. However, in the present invention, the call quality using the wireless LAN is improved by minimizing the influence of the external interference signal. The call quality index may be calculated using a possible signal-to-noise ratio (SNR) or a carrier-to-noise ratio (CNR), or a bit error rate (BER), which is the ratio of errors occurring during the data transmission process due to the external interference signal, is used. Thus, it may be possible to calculate the call quality index.

When the call quality index is calculated as described above, the call quality satisfaction level can be calculated by comparing the call quality index with a predetermined call quality reference value. The call quality satisfaction level may be used as data for determining a level of call quality compared to an appropriate call quality level when a call is conducted in a current wireless LAN operation mode.

Next, the operation mode determination step (S340) of determining whether or not to change the wireless LAN protocol and the contents of the change in the terminal by reflecting the call quality satisfactory level is examined. In this step, it is determined whether to change the wireless LAN protocol in consideration of the call quality satisfaction level calculated in the previous step (S330), and further, when changing the wireless LAN protocol, it is determined which protocol to change to.

First, in determining whether to change the wireless LAN protocol, it can be determined in consideration of the calculated call quality satisfaction level. For example, if the calculated call quality satisfaction level does not meet a predetermined reference value, the wireless LAN protocol is You can decide to change it. Further, the predetermined reference value may be a fixed value, but may vary depending on the settings of the WLAN operation mode such as the protocol and data transmission rate currently in use. Considering whether it is a place, etc., it can be made to have a flexible value.

In FIG. 4, specifications such as various wireless LAN protocols according to the 802.11 standard and data rates and operating frequencies according to each wireless LAN protocol are presented. As can be seen in FIG. 4, protocols of various characteristics, such as 802.11b, 802.11a, 802.11g, 802.11n, and 802.11ac, are standardized in the wireless LAN protocol. In general, it can be seen that recently standardized protocols such as 802.11ac have a high data transmission rate in consideration of the demand for high-speed wireless communication, whereas protocols in the early stages of standardization such as 802.11b have a rather low data transmission rate. have.

However, in the case of a call system using a wireless LAN, it is important to minimize the effect of external interference signals while maintaining the data transmission speed only above the level necessary for the call, rather than a high data transmission rate in order to increase the call quality. It can be said. Therefore, in the present invention, the operation mode of a wireless LAN (WiFi), which is normally operated to maintain a high data rate, is changed to a direction in which call quality can be improved when a call is made using a wireless LAN. do.

First, when it is decided to change the wireless LAN protocol, it is further determined which wireless LAN protocol to change. In this case, a protocol to be changed may be selected in consideration of the calculated call quality satisfaction level, or in some cases, a protocol to be changed may be changed to a predetermined protocol.

First, in the case of selecting a protocol to be changed in consideration of the calculated call quality satisfaction level, a wireless LAN having a maximum data rate lower than the maximum data rate in the wireless LAN protocol at the time of call initiation. You can change it to the protocol. For example, if the protocol currently being used is 802.11ac and the level of meeting quality does not meet a predetermined reference value at the time of starting a call, the wireless LAN protocol may be changed to 802.11n. As described above, 802.11ac can have a data transmission rate of up to 867 Mbps as shown in Fig. 4, whereas 802.11n can have a maximum data transmission rate of 150 Mbps, and other protocols such as 802.11g can have a data transmission rate of up to 54 Mbps. It supports transmission speed. Therefore, it is possible to step down by changing to 802.11n, a wireless LAN protocol having a maximum data transmission rate lower than 856.7Mbps of 802.11ac, which is a wireless LAN protocol at the time of call initiation. At this time, the modulation method used in each standard is also changed, and as data at a lower speed is transmitted, it is possible to suppress a problem in which data transmission is delayed or lost due to an external interference signal. In addition, if necessary, it is possible to repeatedly change the wireless LAN protocol in consideration of call quality.

Further, when the call quality satisfactory level is significantly less than a predetermined reference value, it may be changed to a predetermined protocol. For example, you can choose to change the wireless LAN protocol to 802.11b. 802.11b has a maximum data rate of only 11 Mbps, but this data rate is a sufficient value for a data rate for voice or video calls. I can.

In particular, in the case of other wireless LAN protocols including 802.11a/g, the maximum data transmission rate is 54 Mbps or more, whereas the 802.11b protocol has a maximum data transmission rate of only 11 Mbps and a relatively high transmission power is used. Therefore, it is possible to minimize the influence of the external interference signal. Therefore, in the case of a terminal optimized for a voice/video call using a wireless LAN, the protocol of the wireless LAN operation mode is changed to 802.11b at the time of call start without considering other conditions, so that the call quality is compared with other wireless LAN protocols. It can be an effective way to greatly improve your performance.

Subsequently, in the step of changing the wireless LAN protocol (S350), when it is determined to change the wireless LAN protocol through the previous series of steps, and the wireless LAN protocol to be changed is selected, the task of changing to the selected wireless LAN protocol is performed. do. Since this step can be carried out without any particular difficulty according to the conventional technique, it will not be examined in detail here.

Finally, the step of changing to a wireless LAN protocol determined according to a predetermined criterion at the end of the call (S360) is reviewed. In this step, when the user ends the call, there is no need to maintain a protocol having a low data transmission rate such as 802.11b, and the user may want a high-speed wireless communication environment. The wireless LAN protocol to be changed may be determined and changed according to a predetermined standard, such as returning to the protocol or a protocol supporting the highest data transmission rate at the time of the call termination. Through this step, the user can conveniently set the wireless LAN operation environment by using the wireless LAN operation environment optimized for the call when making a call using the wireless LAN, and setting the appropriate wireless LAN operation environment again at the end of the call. You will be able to.

Furthermore, when the user desires to continuously use a call using a wireless LAN, the protocol set at the time of a call such as 802.11b may be maintained even after the call is terminated.

Previously, in a call using a wireless LAN, a method of providing a stable call environment to a user by appropriately changing a wireless LAN protocol was examined. However, as shown in FIG. 4, even if the same protocol is used, the data transmission speed can be variously changed. By changing the data transmission speed together with the wireless LAN protocol, a more stable wireless LAN is provided to the user. It is possible to provide a used currency environment.

For example, even if the same 802.11b protocol is used, the data transmission rate can be used not only of 11 Mbps, but also 5.5, 2, and 1 Mbps, so that the data transmission speed is within the range allowed by the data transmission speed required by the terminal. By lowering it, a more stable call environment can be provided to the user.

More specifically, after calculating the sum of the data rate in the wireless LAN used by the terminal at the start of the call and the data rate additionally generated by the call, the call start time Among the data transmission speed standards having a data transmission rate greater than the summation value in the wireless LAN protocol of, it may be changed to the smallest data transmission rate standard.

For example, if a user is using 2Mbps for content download, but an external call is made and a call is initiated using a wireless LAN, if the data transmission speed required for a voice call is 100 kbps, download the content and make a voice call. The data transmission speed required for this will be 2.1 Mbps in total, so it is possible to select a data transmission rate of 5.5 Mbps or 11 Mbps in the 802.11b protocol. It can be changed to the data rate standard.

Further, a data rate value corresponding to data that is stopped due to the call may be subtracted from the data rate in the wireless LAN used by the terminal at the start time of the call. For example, if a user is using 2Mbps while downloading content using a smartphone and using 500kbps for web surfing, and an external call is made and a call is initiated using a wireless LAN, the user Since surfing will be stopped, the corresponding data rate value can be subtracted. Accordingly, if the data transmission rate required for a voice call is 100 kbps, the sum of 2 Mbps for content download and 100 kbps for a voice call may be a sum of 2.1 Mbps.

5 shows a flowchart of a high-quality call method by changing a wireless LAN protocol and a data rate according to an embodiment of the present invention. As can be seen in FIG. 5, a step similar to the high-quality call method through the wireless LAN protocol change of FIG. 3 is performed previously, but a more stable call to the user by considering the change of the protocol and data rate together. It will be able to provide an environment.

More specifically, in the high-quality call method by changing a wireless LAN protocol and a data rate according to an embodiment of the present invention, the terminal accessing a wireless LAN (WiFi) access point (S510), In step S520 of initiating a call at the terminal, the call quality index in the case of conducting a call using the WLAN protocol at the time of the call initiation is calculated according to a predetermined standard, and then the call quality is compared with a predetermined call quality reference value. Call quality determination step (S530) of determining the satisfaction level, operation mode determination step (S540) of determining whether or not to change the wireless LAN protocol in the terminal by reflecting the call quality satisfaction level (S540), reflecting the call quality satisfaction level The operation mode determination step (S550) of determining whether or not to change the wireless LAN data transmission rate and the contents of the change in the terminal (S550), changing the wireless LAN protocol/data transmission rate (S560), and determined according to a predetermined criterion at the end of the call It may be configured to include a step (S570) of changing the wireless LAN protocol/data transmission rate.

Here, the high quality through the wireless LAN protocol change of FIG. 3 is added, except that the operation mode determination step (S550) of determining whether or not to change the wireless LAN data transmission rate and the contents of the change in the terminal by reflecting the call quality satisfactory level is added. It can be seen that it is similar to the calling method. In this step S550, by reflecting the call quality satisfaction level, the terminal determines whether to change the wireless LAN data transmission rate and the contents of the change, and changes the data transmission rate along with the wireless LAN protocol as described above, so that the user can be more stable It is possible to provide a call environment using a wireless LAN.

In addition, FIG. 6 shows a flowchart of a high-quality call method through a wireless LAN protocol and channel change according to an embodiment of the present invention. As can be seen in FIG. 6, similar to the case of the high-quality call method by changing the wireless LAN protocol and data rate of FIG. 5, a call using a wireless LAN by changing a wireless LAN channel together with a wireless LAN protocol. It will be possible to improve the environment more stably.

As shown in FIG. 2, the channel in the WLAN may interfere with each other as some frequency bands overlap each other, and since the frequency band of the WLAN is an ISM band, which is an open common frequency band, there is a possibility that an external interference signal may occur. It is done. Therefore, by using one or more of signal-to-noise ratio (SNR), carrier-to-noise ratio (CNR), and bit error rate (BER) in each channel, the communication environment using a wireless LAN is more improved by changing to a channel that satisfies a predetermined reference value. You will be able to improve.

More specifically, in the high-quality call method by changing the wireless LAN protocol and data rate according to an embodiment of the present invention, the terminal accessing a wireless LAN (WiFi) access point (S610), In the step of starting a call at the terminal (S620), the call quality index when the call is conducted using the WLAN protocol at the time of the call initiation is calculated according to a predetermined criterion, and then the call quality is compared with a predetermined call quality reference value. Call quality determination step (S630) of determining the satisfaction level, operation mode determination step (S640) of determining whether or not to change the wireless LAN protocol in the terminal by reflecting the call quality satisfaction level (S640), reflecting the call quality satisfaction level The operation mode determination step (S650) of determining whether to change the wireless LAN channel and the contents of the change in the terminal (S650), the step of changing the wireless LAN protocol/channel (S660), the wireless LAN protocol determined according to a predetermined criterion at the end of the call It can be configured including the step of changing to the /channel (S670).

In this case, as compared with the high-quality call method through changing the wireless LAN protocol and data rate shown in FIG. 5 above, the contents of changing the wireless LAN data transmission rate have changed the contents of changing the wireless LAN channel. Since there is no great difficulty in understanding and carrying out the present invention by making a similar configuration, a detailed description will be omitted.

7 shows a configuration diagram of a terminal 700 having a call function using a wireless LAN according to an embodiment of the present invention. As can be seen in FIG. 7, the terminal 700 having a call function using a wireless LAN according to an embodiment of the present invention is a wireless LAN communication unit that accesses a wireless LAN (WiFi) through an access point. 710), a call unit 720 that provides a call function with another terminal, and a call quality index when a call is conducted using a wireless LAN operation mode at the time of call initiation is calculated according to a predetermined standard, and then determined in advance. A call quality determination unit 730 that determines a call quality satisfaction level by comparing it with a true call quality reference value, and an operation mode determination unit that determines whether or not to change the WLAN operation mode in the terminal by reflecting the call quality satisfaction level ( 740). In this case, a wireless LAN protocol is included in the wireless LAN operation mode.

Hereinafter, each component of the terminal 700 having a call function using a wireless LAN according to an embodiment of the present invention is divided and examined in detail.

First, the wireless LAN communication unit 710 is reviewed. The wireless LAN communication unit connects to a wireless LAN (WiFi) through an access point so that a user can make a voice or video call with a user of another terminal using the wireless LAN. Since the wireless LAN communication unit 710 can be implemented and operated without great difficulty according to the prior art, it is not examined in detail here.

Next, look for the call unit 720. The call unit 720 provides a voice call or a video call using a wireless LAN connected through the wireless LAN communication unit 710 using a VoIP (Voice on Internet Protocol) or the like. The call unit 720 can also be implemented and operated without great difficulty according to the prior art, so it is not examined in detail here.

Subsequently, the call quality determination unit 730 measures the call quality index when the current terminal makes a call using a wireless LAN, and compares the call quality index with a predetermined call quality reference value to determine the level of call quality satisfaction. It is done. In particular, since the frequency environment of the wireless LAN may be changed from time to time, it is desirable to measure the call quality index again at the time of starting the call. More specifically, it is possible to calculate a call quality index using at least one of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in the WLAN operation mode at the time of the call start.

Subsequently, the operation mode determination unit 740 is examined. The operation mode determination unit 740 determines whether or not to change the wireless LAN operation mode and the contents of the change in the terminal by reflecting the call quality satisfaction level. In this case, various algorithms may be used to determine whether or not to change the WLAN operation mode and the contents of the change. Hereinafter, various algorithms of operation mode change in the operation mode determination unit 740 will be examined.

First, the operation mode determining unit 740 may determine to change to a wireless LAN protocol having a maximum data rate lower than a maximum data rate in the wireless LAN protocol at the time of initiating a call. Accordingly, it is possible to gradually lower the wireless LAN protocol at the time of starting a call to a wireless LAN protocol having a lower maximum data rate. At this time, the modulation method used in each standard is also changed, and as data at a lower speed is transmitted, it is possible to suppress a problem in which data transmission is delayed or lost due to an external interference signal. In addition, if necessary, it is possible to repeatedly change the wireless LAN protocol in consideration of call quality.

In addition, the operation mode determination unit 740 may change the protocol of the wireless LAN operation mode to be changed to 802.11b without considering other conditions. In particular, 802.11b has a maximum data rate of only 11Mbps, but it can be said to be a sufficient value for a data rate for voice or video calls. Also, since it uses a relatively high value for transmission power, it is affected by external interference signals. Can be minimized. Therefore, in the case of a terminal optimized for a voice/video call using a wireless LAN, the protocol of the wireless LAN operation mode is changed to 802.11b at the time of call start without considering other conditions, so that the call quality is compared with other wireless LAN protocols. Can be greatly improved.

In addition, the operation mode determination unit 740 calculates the sum of the data rate in the wireless LAN used by the terminal at the time of the call start and the data rate additionally generated by the call. After that, it may be determined to change to the smallest data rate standard among the data rate standards having a data rate greater than the sum value in the WLAN protocol at the time of the call start time. That is, the call quality is improved by lowering the data rate as much as possible within a range capable of satisfying the data rate according to the amount of data transmission in the wireless LAN used at the start of a call. Accordingly, the wireless LAN operation mode further includes a wireless LAN data rate, and when the operation mode determination unit 740 changes the operation mode, the wireless LAN data rate is changed.

Furthermore, by subtracting the data rate value corresponding to the data that is stopped due to the call from the data rate in the wireless LAN used by the terminal at the start of the call, The operation mode may be determined based on the minimum data rate.

At this time, the operation mode determination unit 740 searches for a channel that satisfies a predetermined reference value by using at least one of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in each channel. Afterwards, you can change to an appropriate channel.

In addition, when the call is terminated, the operation mode may be restored to the WLAN operation mode at the time when the call is initiated, or the operation mode may be changed to the WLAN operation mode determined according to a predetermined criterion at the time when the call is terminated. For example, it is possible to change to a wireless LAN protocol that supports the highest data rate supported by the terminal.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains will be able to make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the embodiments described in the present invention are not intended to limit the technical idea of the present invention, but to explain it, and are not limited to these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

700: a terminal having a call function using a wireless LAN
710: wireless LAN communication unit
720: currency department
730: call quality determination unit
740: operation mode determination unit

Claims (16)

Accessing, by the terminal, a wireless LAN (WiFi) access point;
Initiating a call at the terminal;
Call quality determination step of determining the level of meeting call quality by calculating a call quality index in case of conducting a call using the WLAN operation mode at the time of call initiation according to a predetermined standard, and comparing it with a preset call quality standard value. ; And
And an operation mode determining step of determining whether or not to change the wireless LAN operation mode and the contents of the change in the terminal by reflecting the call quality satisfaction level,
The wireless LAN operation mode includes a wireless LAN protocol,
In the operation mode determining step,
After calculating the sum of the data rate in the wireless LAN used by the terminal at the start of the call and the data rate additionally generated by the call,
A call method using a wireless LAN, characterized in that it is determined to change to the smallest data transmission speed standard among data transmission speed standards having a data transmission rate greater than the sum in a wireless LAN protocol at a call start point. The method of claim 1,
In the call quality determination step,
A call method using a wireless LAN, characterized in that the call quality index is calculated using at least one of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in a wireless LAN operation mode at the time of call initiation. . The method of claim 1,
In the operation mode determining step,
A call method using a wireless LAN, characterized in that it is determined to change to a wireless LAN protocol having a maximum data rate lower than a maximum data rate in the wireless LAN protocol at the time of starting the call. The method of claim 1,
In the operation mode determining step,
A call method using a wireless LAN, characterized in that determining to change a protocol of a wireless LAN operation mode to be changed to 802.11b without considering other conditions. The method of claim 1,
The wireless LAN operation mode further includes a wireless LAN data rate. The method of claim 5,
A wireless LAN, characterized in that a data rate value corresponding to data whose transmission is stopped due to the call is subtracted from the data rate in the wireless LAN used by the terminal at the time of the call initiation. Call method used. The method of claim 1,
In the operation mode determining step,
Using one or more of signal-to-noise ratio (SNR), carrier-to-noise ratio (CNR), and bit error rate (BER) in each channel,
It is decided to change to a channel that meets a predetermined standard value,
In this case, the wireless LAN operation mode further includes a wireless LAN channel. The method of claim 1,
When the call ends at the terminal,
Return to the wireless LAN operation mode at the time the call was initiated, or
And changing to a wireless LAN operation mode in which the call quality index satisfies a predetermined reference value at the end of the call. A wireless LAN communication unit for accessing a wireless LAN (WiFi) through an access point;
A call unit that provides a call function with another terminal;
A call quality determination unit that calculates the call quality index in the case of conducting a call using the WLAN operation mode at the time of call initiation according to a predetermined standard, and then compares it with a predetermined call quality standard value to determine the level of call quality satisfaction. ;
An operation mode determination unit for determining whether or not to change a wireless LAN operation mode and a change content in the terminal by reflecting the call quality satisfaction level,
The wireless LAN operation mode includes a wireless LAN protocol,
In the operation mode determination unit,
After calculating the sum of the data rate in the wireless LAN used by the terminal at the start of the call and the data rate additionally generated by the call,
A terminal having a call function using a wireless LAN, characterized in that it is determined to change to the smallest data transmission speed standard among data transmission speed standards having a data transmission rate greater than the sum in a wireless LAN protocol at a call start time. The method of claim 9,
In the call quality determination unit,
A call function using a wireless LAN, characterized in that the call quality index is calculated using one or more of a signal-to-noise ratio (SNR), a carrier-to-noise ratio (CNR), and a bit error rate (BER) in a wireless LAN operation mode at the time of call initiation. Terminal with. The method of claim 9,
In the operation mode determination unit,
A terminal having a call function using a wireless LAN, characterized in that it is decided to change to a wireless LAN protocol having a maximum data rate lower than the maximum data rate in the wireless LAN protocol at the time of call initiation. . The method of claim 9,
In the operation mode determination unit,
A terminal having a call function using a wireless LAN, characterized in that determining to change a protocol of a wireless LAN operation mode to be changed to 802.11b without considering other conditions. The method of claim 9,
The terminal having a call function using a wireless LAN, characterized in that the wireless LAN operation mode further includes a wireless LAN data rate. The method of claim 13,
A wireless LAN, characterized in that a data rate value corresponding to data whose transmission is stopped due to the call is subtracted from the data rate in the wireless LAN used by the terminal at the time of the call initiation. A terminal having a used call function. The method of claim 9,
In the operation mode determination unit,
Using one or more of signal-to-noise ratio (SNR), carrier-to-noise ratio (CNR), and bit error rate (BER) in each channel,
It is decided to change to a channel that meets a predetermined standard value,
At this time, the terminal having a call function using a wireless LAN, characterized in that the wireless LAN operation mode further includes a wireless LAN channel. The method of claim 9,
When the call ends at the terminal,
Return to the wireless LAN operation mode at the time the call was initiated, or
A terminal having a call function using a wireless LAN, characterized in that the call quality index is changed to a wireless LAN operation mode that satisfies a predetermined reference value at a call end time point.

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