CN102246420B - Mobile terminal and method for reducing internal mutual interference of mobile terminal - Google Patents

Abstract

The invention provides a mobile terminal and a method for reducing internal mutual interference of the mobile terminal. A terminal: the device comprises a mobile communication module, a DECT FP, a main processor, a first filter and a second filter; the mobile communication module is communicated with the GSM; the FP works in a preset frequency band and communicates with the DECT PP; the main processor realizes the communication between the FP and the mobile communication module; the first filter filters DECT signals of a preset frequency band received by the mobile communication module; the second filter filters noise signals transmitted by the FP in a receiving frequency band of the mobile communication module and GSM signals of a preset frequency band received by the FP.

Description

Mobile terminal and method for reducing internal mutual interference of mobile terminal

technical field

The embodiments of the present invention relate to the field of communication technologies, and in particular, to a mobile terminal and a method for reducing internal mutual interference of the mobile terminal. the

Background technique

The mobile terminals in the prior art all have a Subscriber Identity Module (SIM for short) corresponding to one mobile terminal, and there is no extension or sub-unit application, so effective communication sharing cannot be realized. In order to solve this problem, the mobile communication module and the fixed part (Fixed Part, referred to as: FP) of the digital enhanced cordless telephone system (Digital Enhanced Cordless Telecommunications, referred to as: DECT) can be integrated together and set in the mobile terminal. The terminal uses the mobile communication module to access the mobile communication network, and uses the DECT FP to establish communication connections with multiple portable parts (Portable Part, PP for short), so that multiple PPs connected to the DECT FP can pass through the SIM in the mobile terminal. The card communicates with the mobile communication network. the

Since the mobile communication module and DECT FP are both wireless communication modules, both need to transmit and receive wireless signals. When the operating frequency bands of the two are close to each other, there will be a problem of mutual interference. The Global System of Mobile communication (GSM for short: GSM) system works in the frequency band of 900M/1800M in most countries and regions, and adopts frequency division duplex mode. For mobile terminals of the GSM system, its high frequency band The transmitting frequency band of 1800M is 1710.1M～1784.9MHz, and the receiving frequency band is 1805.1M～1879.9MHz. However, the working frequency band of DECT PP in most countries and regions is 1880.928M ~ 1890.208MHz, adopting time division duplex mode, sending and receiving at the same frequency. This makes the receiving frequency band of GSM1800 adjacent to the working frequency band of DECT1800, and there is no guard band. the

Since the working frequency bands are adjacent and there is no guard band, the interference signal between the mobile communication module and DECT cannot be effectively suppressed, and the signal transmitted between the FP and PP of DECT will directly enter the GSM1800 system, interfering with its reception of useful signals, resulting in mobile The receiver of the communication module is blocked. Similarly, the signal transmitted by the mobile communication module will block the signal received by the DECT FP, affecting its normal operation. the

Contents of the invention

The embodiment of the present invention provides a mobile terminal and a method for reducing internal mutual interference of the mobile terminal, so as to solve the problem of mutual interference between the mobile communication module and the DECT FP in the mobile terminal integrated with the mobile communication module and the DECT FP in the prior art. the

An embodiment of the present invention provides a mobile terminal, including: a mobile communication module, a fixed part FP of a digital enhanced cordless telephone system DECT, a main processor, a first filter and a second filter;

The mobile communication module is used to communicate with the Global System for Mobile Communications GSM;

The FP works in a predetermined frequency band and is used to communicate with the portable part PP of DECT;

The main processor is connected to the mobile communication module and the FP respectively, and is used to realize the communication between the FP and the mobile communication module;

The first filter is electrically connected to the mobile communication module, and is used to filter out the DECT signal of the predetermined frequency band received by the mobile communication module;

The second filter is electrically connected to the FP of the DECT, and is used to filter out the noise signal emitted by the FP within the receiving frequency band of the mobile communication module and the GSM signal of the predetermined frequency band received by the FP . the

The predetermined frequency range is between the first predetermined frequency point and the second predetermined frequency point, the first predetermined frequency point is smaller than the second predetermined frequency point, the first predetermined frequency point is greater than 1880MHz, and the second predetermined frequency point is greater than 1880MHz. The frequency point is less than or equal to 1900MHz. the

An embodiment of the present invention provides a method for reducing internal mutual interference of a mobile terminal, including:

Filter out the DECT signal of the predetermined frequency band received by the mobile communication module through a first filter connected to the mobile communication module;

The second filter connected to the FP filters out the noise signal transmitted by the FP within the receiving frequency band of the mobile communication module and the GSM signal of the predetermined frequency band received by the FP. the

The predetermined frequency range is between the first predetermined frequency point and the second predetermined frequency point, the first predetermined frequency point is smaller than the second predetermined frequency point, the first predetermined frequency point is greater than 1880MHz, and the second predetermined frequency point is greater than 1880MHz. The frequency point is less than or equal to 1900MHz. the

The mobile terminal of the embodiment of the present invention and the method for reducing the internal mutual interference of the mobile terminal limit the DECT to work in a predetermined frequency band, and then filter out the DECT of the predetermined frequency band received by the mobile communication module through the first filter connected to the mobile communication module The signal is filtered through the second filter connected to the FP of the DECT to filter out the noise signal sent by the DECT within the frequency band received by the mobile communication module and the GSM signal of the predetermined frequency band received by the FP. The mutual interference between the mobile communication module inside the mobile terminal and the DECT is effectively reduced. the

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work. the

Fig. 1 is a schematic structural diagram of a mobile terminal provided by an embodiment of the present invention;

Fig. 2 is a flowchart of a method for reducing internal mutual interference of a mobile terminal provided by an embodiment of the present invention. the

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention. the

Fig. 1 is a schematic structural diagram of a mobile terminal provided by an embodiment of the present invention. As shown in Fig. 1, the mobile terminal includes: a mobile communication module 101, an FP102 of DECT, a main processor 103, a first filter 104 and a second filter device 105. Wherein, mobile communication module 101 is used for communicating with GSM, and FP102 of DECT works in predetermined frequency band, is used for communicating with each PP201 of DECT, main processor 103 is connected with mobile communication module 101 and FP102 respectively, is used for realizing FP102 and FP102 The communication between the mobile communication modules 101, the first filter 104 is electrically connected with the mobile communication module 101, used to filter out the DECT signal in the predetermined frequency band received by the mobile communication module 101, the second filter 105 and the FP102 of DECT The electrical connection is used to filter out the noise signal transmitted by FP102 and PP201 within the receiving frequency band of the mobile communication module 101 and the GSM signal within the predetermined frequency band received by FP102. Wherein, the first filter 104 may be electrically connected to the antenna of the mobile communication module 101 , and the second filter 105 may be electrically connected to the antenna of the FP102 . the

The noise signal transmitted by DECT in the receiving frequency band of the mobile communication module 101 can be understood as: Assuming that the operating frequency of the DECT transmitted signal is 1890MHz, and the actual transmitted signal is outside 10MHz, that is, at a place of 1880M, there will also be a signal. Of course, this signal is not The power of 1890M is so big. The signal with a small difference between the operating frequency and 1880M can be understood as a noise signal, or it can also be called a spurious signal. the

It should be noted that the DECT signal is an interaction signal between FP102 and PP201, and for the mobile communication module 101, the working frequency band of the DECT signal is the working frequency band specified by the standards organization. In the embodiment of the present invention, a frequency band is selected as the predetermined frequency band in the working frequency band of the DECT signal. The predetermined frequency band can be from the first predetermined frequency point to the second predetermined frequency point, and the first predetermined frequency point is smaller than the second predetermined frequency point. . In order to ensure that there is a certain guard band between the working frequency band of DECT and the receiving frequency band of the mobile communication module 101, the first predetermined frequency point needs to be greater than 1880 MHz. The selection of the first predetermined frequency point may be determined according to the size of the guard band, for example, if the guard band is 10 MHz, then the first predetermined frequency point may be selected as 1890 MHz. The second predetermined frequency point may be less than or equal to 1900 MHz, preferably 1900 MHz. the

In a preferred implementation manner, the passband of the first filter 104 is the signal of the GSM receiving frequency band 1805MHz-1880MHz, and the stopband is the signal of 1890MHz-1900MHz sent by the DECT. The passband of the second filter 105 is the signal in the DECT working frequency range of 1890MHz-1900MHz, and the stopband is the signal of 1805MHz-1880MHz and 1705MHz-1880MHz. the

Among them, the second filter 105 needs to suppress the noise signal generated by the DECT transmission and falls at 1805MHz-1880MHz. After the noise signal is received by the mobile communication module 101, co-channel interference will be generated. In addition, the second filter 105 also needs to suppress the signal transmitted by the mobile communication module 101 at 1705MHz-1880MHz. Although this signal is not in the DECT working frequency band, because the signal power is too large, if the front end of the DECT receiver does not have sufficient suppression, it will still be Will cause the DECT front-end receiver to saturate. the

DECT FP102 and its multiple PP201 work in a predetermined frequency band, and there may be multiple available channels in this frequency band. PP201 and FP102 preferably use the channel with the highest frequency point among the available channels in the predetermined frequency band. Taking the predetermined frequency band from 1890MHz to 1900MHz as an example, in this frequency band, the number of available channels is 5, and the frequency points are respectively recorded as channel 0, channel 1, channel 2, channel 3 and channel 4 from high to low. It should be noted that the channel number and the corresponding specific working frequency are stipulated by the standard organization, for example, channel 0 is 1897.344 MHz, and channel 5 is 1888.704 MHz. The FP 102 of DECT and its plurality of PP 201 then preferably use channel 0. the

When it is necessary to switch channels, for example, the signal quality of the current channel is unacceptable or there is interference in the current channel, it is necessary to reselect the channel and select an available channel that meets the conditions for establishing a connection, such as an available channel with good signal quality and low interference; or there is a new Some users need to occupy a new channel and need to re-apply for a channel. DECT's FP102 and its multiple PP201s will gradually switch to lower-frequency channels to reduce the impact of system mutual interference. the

Specifically, FIG. 2 is a flow chart of a method for reducing internal mutual interference of a mobile terminal provided by an embodiment of the present invention. The mobile terminal shown in FIG. 2 may refer to the mobile terminal provided in the foregoing embodiment, and details are not described here. As shown in Figure 2, the method includes:

Step 201: PP201 and FP102 negotiate the working channel, that is, establish a connection on channel N;

Wherein, channel N is an available channel working in a predetermined frequency band. The initial value of N starts from the value corresponding to the channel with the highest frequency within the allowable range. the

The predetermined frequency band may be between the first predetermined frequency point and the second predetermined frequency point, and the first predetermined frequency point is smaller than the second predetermined frequency point. In order to ensure that there is a certain guard band between the working frequency band of DECT and the receiving frequency band of the mobile communication module 101, the first predetermined frequency point needs to be greater than 1880 MHz. The selection of the first predetermined frequency point can be determined according to the size of the guard band, for example, if the guard band is 10MHz, then the first predetermined frequency point can be selected as 1890MHz. The second predetermined frequency point may be less than or equal to 1900 MHz, preferably 1900 MHz. the

Taking the predetermined frequency band from 1890MHz to 1900MHz as an example, in this frequency band, the number of available channels is 5, and the frequency points are respectively recorded as channel 0, channel 1, channel 2, channel 3 and channel 4 from high to low. It should be noted that the channel number and the corresponding specific working frequency are stipulated by the standard organization, for example, channel 0 is 1897.344 MHz, and channel 5 is 1888.704 MHz. In this embodiment, channel 0 is preferably used. the

Step 202: PP201 and FP102 determine whether to establish a connection on the channel N according to the environment;

If yes, establish a connection on channel N, and end this method;

If not, go to step 203 . the

Wherein, determining whether to establish a connection on the N channel according to the environment may include: detecting whether there is interference on the frequency point of the channel N, the signal quality, and the like. If there is interference or the signal quality is not very good, no connection is established on channel N, that is, channel N is an available channel that does not meet the establishment conditions. It should be noted that how to judge the signal quality has specific evaluation criteria stipulated in the DECT protocol, see ETSIETR 310 [9] for details, and will not be repeated here. the

Step 203: The value corresponding to the channel with the second highest frequency point within the allowable range is used as the number of N, and step 201 is executed. the

The mobile terminal and the method for reducing the internal mutual interference of the mobile terminal provided by the embodiments of the present invention limit DECT to work in a predetermined frequency band, and then filter out the predetermined frequency band received by the mobile communication module through the first filter connected to the mobile communication module. The DECT signal, through the second filter connected to the FP of DECT, filters out the noise signal sent by DECT in the mobile communication module receiving frequency band and the GSM signal of the predetermined frequency band received by FP, effectively reducing the internal mobile communication module of the mobile terminal. mutual interference between. the

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above-mentioned method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes. the

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention. the

Claims (8)

1. A mobile terminal, characterized in that it comprises: a mobile communication module, a fixed part FP of a digital enhanced cordless telephone system DECT, a main processor, a first filter and a second filter; The mobile communication module is used to communicate with the Global System for Mobile Communications GSM; The FP works in a predetermined frequency band and is used to communicate with the portable part PP of DECT; The main processor is connected to the mobile communication module and the FP respectively, and is used to realize the communication between the FP and the mobile communication module; The first filter is electrically connected to the mobile communication module, and is used to filter out the DECT signal of the predetermined frequency band received by the mobile communication module; The second filter is electrically connected to the FP of the DECT, and is used to filter out the noise signal emitted by the FP within the receiving frequency band of the mobile communication module and the GSM signal of the predetermined frequency band received by the FP ; The predetermined frequency range is between the first predetermined frequency point and the second predetermined frequency point, the first predetermined frequency point is smaller than the second predetermined frequency point, the first predetermined frequency point is greater than 1880MHz, and the second predetermined frequency point is greater than 1880MHz. The frequency point is less than or equal to 1900MHz. 2. The mobile terminal according to claim 1, wherein the first filter is electrically connected to the antenna of the mobile communication module; the second filter is electrically connected to the antenna of the FP. 3. The mobile terminal according to claim 1 or 2, wherein the working channels of the PP and FP of the DECT are: the channel with the highest frequency point among the available channels in the predetermined frequency band. 4. The mobile terminal according to claim 1, wherein the first predetermined frequency point is 1890 MHz, and the second predetermined frequency point is 1900 MHz. 5. A method for reducing the internal mutual interference of the mobile terminal according to any one of claims 1 to 4, characterized in that it comprises: filtering out the DECT signal of the predetermined frequency band received by the mobile communication module through a first filter connected to the mobile communication module; Filter out the noise signal transmitted by the FP in the receiving frequency band of the mobile communication module and the GSM signal of the predetermined frequency band received by the FP through the second filter connected to the FP; The predetermined frequency range is between the first predetermined frequency point and the second predetermined frequency point, the first predetermined frequency point is smaller than the second predetermined frequency point, the first predetermined frequency point is greater than 1880MHz, and the second predetermined frequency point is greater than 1880MHz. The frequency point is less than or equal to 1900MHz. 6. method according to claim 5, is characterized in that, also comprises before described method: The FP negotiates a working channel with the PP, and the working channel is an available channel in the predetermined frequency band. 7. The method according to claim 5 or 6, wherein the FP and the PP select the channel with the highest frequency point as the working channel among the available channels meeting the conditions for establishing a connection. 8. The method according to claim 5, wherein the first predetermined frequency point is 1890 MHz, and the second predetermined frequency point is 1900 MHz.

Images