CN102055822A - Mobile phone - Google Patents

Abstract

The invention discloses a mobile phone, which includes a printed circuit board. Antennas and speakers are respectively arranged at both ends of the printed circuit board. A choke sleeve, the choke sleeve is arranged on the radio frequency induction current path conducted from the antenna to the speaker, and the choke sleeve is connected to the common ground wire of the printed circuit board. In the present invention, a choke sleeve is provided on the radio frequency induction current path conducted from the antenna to the speaker, and the choke sleeve is connected to the common ground wire of the printed circuit board, which is equivalent to the above-mentioned radio frequency induction current path Connecting an infinite resistor in series improves the HAC compatibility of the mobile phone, reduces the interference noise caused by the mobile phone and the hearing aid, and has no effect on the radiation performance of the antenna itself.

Description

a mobile phone

technical field

The invention relates to the communication field, in particular to a mobile phone compatible with hearing aids.

Background technique

HAC phones are hearing aid compatible phones. The full name of HAC is Hearing Aid Compatibility, which is a standard for mobile phones to support hearing aid compatibility. In North America and Europe, most well-known mobile phone manufacturers and communication equipment suppliers provide mobile phones with very little radiation and frequency interference, and they are compatible with hearing aid inductors or microphones. HAC involves two compatibility coefficients "M" and "T", ("M" is the compatibility for the microphone; "T" is the compatibility for the induction coil). The interference of the mobile phone to the hearing aid microphone meets the M4 level, that is, the least interference; the inductance compatibility coefficient reaches the T4 level, that is, the built-in inductive circuit of the hearing aid is the best compatible with the mobile phone.

At present, the FCC in the United States enforces the HAC certification plan for mobile phone manufacturers. The reference standard for HAC certification is ANSI C63.19 (the national standard method for measuring the compatibility of wireless communication equipment and hearing aids in the United States). According to the definition of this standard, consumers can judge the compatibility of a certain type of hearing aid with mobile phones by the anti-interference level of hearing aids and the corresponding mobile phone signal emission level.

As shown in FIG. 1 , the mobile phone antenna 1 in the prior art is located at the upper end of the printed circuit board 2 , the speaker 3 is located at the lower end of the printed circuit board 2 , and the HAC test area 4 covers the area of the speaker 3 . That is, the existing mobile phone antenna is usually located at one end of the printed circuit board, and the speaker is placed at the other end of the printed circuit board. The purpose is to reduce the radio frequency electric field and magnetic field in the HAC test area by increasing the distance between the mobile phone antenna and the speaker. strength. But when the mobile phone antenna is working, not only the antenna radiator itself generates radio frequency current, but also induces radio frequency induced current on the printed circuit board, and the radio frequency induced current will also participate in the radiation of radio frequency energy, and the radio frequency induced current is cut off at the lower end of the printed circuit board , that is, the radio frequency induced current is cut off at one end of the speaker, and the intensity of the radio frequency induced current decreases to zero, which means the accumulation of charges, and the time-varying charges generate an induced electric field here, and at the same time, this changing electric field will generate a corresponding induced magnetic field , the induced electric field and induced magnetic field generated are just located in the test area of the HAC, forming interference noise, and the RF induced current 5 conducted from the mobile phone antenna 1 to the speaker 3 has the most prominent interference on the hearing aid. Therefore, under the length of the existing mobile phone, the distance between the mobile phone antenna and the speaker cannot completely solve the problem of HAC compatibility.

This shows that the prior art needs further improvement and development.

Contents of the invention

The present invention provides a mobile phone to solve the above defects in the prior art, solve the interference of the induced electric field and the induced magnetic field formed by the radio frequency induced current on the hearing aid, improve the HAC compatibility of the mobile phone, and reduce the interference noise caused by the mobile phone and the hearing aid.

In order to solve the problems of the technologies described above, the solution of the present invention includes:

A mobile phone, which includes a printed circuit board. Antennas and speakers are respectively arranged at both ends of the printed circuit board, wherein a choke sleeve is arranged on the printed circuit board between the antenna and the speaker, and the choke sleeve The flow sleeve is arranged on the path of the radio frequency induction current conducted from the antenna to the speaker, and the flow sleeve is connected to the common ground wire of the printed circuit board.

In the mobile phone, the choke sleeve includes two open lines operating at the center frequency of the high frequency band and having a length of one quarter of the wavelength of the center frequency, which are respectively arranged on the corresponding board edges of the printed circuit board.

The mobile phone, wherein, one end of the open line is connected to the common ground line, and the remaining part faces one end of the printed circuit board provided with the antenna, along the length direction of the corresponding board edge of the printed circuit board Arranged, there is a gap between the remaining part and the corresponding board edge, and the remaining part and the printed circuit board form a quarter-wavelength resonator.

The mobile phone, wherein, the printed circuit board is provided with a Bluetooth module and a WIFI antenna module, and the two open lines are respectively equipped with a single-pole double-throw switch, and the open line is connected to the active contact of the corresponding single-pole double-throw switch. The bluetooth module and the common ground wire are respectively connected to the corresponding fixed contacts of a single-pole double-throw switch, and the WIFI module and the common ground wire are respectively connected to the corresponding fixed contacts of another single-pole double-throw switch.

In the mobile phone, a baseband chip for controlling the connection direction of two single-pole double-throw switches is arranged on the printed circuit board, and the two single-pole double-throw switches are respectively connected in communication with the baseband chip.

The mobile phone, wherein, the interface of the mobile phone is provided with HAC mode and normal mode, the mobile phone is in the HAC mode, and the two open lines are connected to the public ground through the corresponding single-pole double-throw switch; the mobile phone is in the said HAC mode In the normal mode, one open line is connected to the Bluetooth module through a corresponding SPDT switch, and the other open line is connected to the WIFI module through a corresponding SPDT switch.

The present invention provides a mobile phone. A choke sleeve is provided on the path of the radio frequency induction current conducted from the antenna to the speaker, and the choke sleeve is connected to the common ground of the printed circuit board, which is equivalent to the above-mentioned An infinite resistor is connected in series with the path of the radio frequency induction current, so the amplitude of the radio frequency induction current will be greatly attenuated when it flows through the open end of the choke sleeve. The strength of the electromagnetic field decreases with the increase of the distance, so the electric field and magnetic field strength in the HAC test area have a large attenuation, which solves the interference of the induced electric field and the induced magnetic field formed by the radio frequency induced current on the hearing aid, and improves the quality of the mobile phone. The HAC compatibility reduces the interference noise caused by mobile phones and hearing aids, and has no effect on the radiation performance of the antenna itself, which is a great progress in the existing technology.

Description of drawings

FIG. 1 is a schematic structural diagram of a printed circuit board of a mobile phone in the prior art.

Fig. 2 is a schematic structural diagram of a printed circuit board with a choke sleeve in the present invention.

Fig. 3 is a simplified structural diagram of multiplexing the choke sleeve and the antenna in the present invention.

Detailed ways

The present invention provides a mobile phone. In order to make the purpose, technical solution and advantages of the present invention clearer and clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

The invention provides a mobile phone. The choke sleeve is arranged on the path of the radio frequency induction current, and the radio frequency induction current is cut off at a position away from the loudspeaker, thereby reducing the interference noise caused by the mobile phone and the hearing aid, and improving the HAC compatibility of the mobile phone. As shown in Figure 2, a mobile phone includes a printed circuit board 101, and the two ends of the printed circuit board 101 are respectively provided with an antenna 102 and a speaker 103, and the printed circuit board can adopt any form in the prior art, so The antenna 102 and the loudspeaker 103 may adopt existing technical forms in the prior art, for example, the antenna 102 may be several antennas.

A choke sleeve 104 is arranged on the printed circuit board 101 between the antenna 102 and the speaker 103, and the choke sleeve 104 is arranged to prevent the radio frequency induction current conducted from the antenna 102 to the speaker 103. On the path 105, the choke sleeve 104 cuts off the radio frequency induced current 105 between the antenna 102 and the speaker 103, so that the radio frequency induced current 105 cannot form an induced electric field and an induced magnetic field near the speaker 103, completely solving the problem It solves the technical problem that the induced electric field and induced magnetic field formed by the radio frequency induced current interfere with the hearing aid, and improves the HAC compatibility of the mobile phone.

As shown in Figure 3, the choke sleeve 104 is connected to the common ground 106 of the printed circuit board 101, which is equivalent to connecting an infinite resistance in series on the radio frequency induction path, so the radio frequency induction current flows through the choke At the open end of the sleeve, the amplitude will be greatly attenuated, which reduces the interference noise caused by mobile phones and hearing aids.

The choke sleeve in the present invention is in the form of an open line, as shown in Figure 2 and Figure 3, the choke sleeve 104 includes two working at the center frequency of the high frequency band, the length of which is a quarter of the wavelength of the center frequency The effect of the open line is equivalent to keeping the loudspeaker 103 away from the antenna 102 by a distance of nearly a quarter wavelength, further weakening the interference of the radio frequency current to the loudspeaker 103 .

The open lines are respectively arranged on corresponding board edges of the printed circuit board 101 . The route opening method has a simple structure, saves the space of the mobile phone, reduces the manufacturing cost of the mobile phone, facilitates the arrangement of more components in the mobile phone, and improves the space utilization rate of the mobile phone.

As shown in Figure 3, the antenna 102 is arranged on the upper end of the printed circuit board 101, the speaker 103 is arranged on the lower end of the printed circuit board 101, and the printed circuit board 101 includes a left board edge 107, a right board The choke sleeve 104 includes a left open line 109 and a right open line 110 , the left open line 109 is set on the left plate edge 107 , and the right open line 110 is set on the right plate edge 108 .

Furthermore, one end of the left open line 109 is connected to the common ground line 106, and the remaining part of the left open line 109 faces the upper end of the printed circuit board 101 along the length of the left board edge 107 Arranged in the direction, there is a gap between the remaining part and the left board edge 107, and the remaining part and the printed circuit board 101 form a quarter-wavelength resonator.

Similarly, one end of the right open line 110 is connected to the common ground 106, and the remaining part of the right open line 110 faces the upper end of the printed circuit board 101 along the length of the right board edge 108 direction, there is a gap between the remaining part and the right board edge 108 , and the remaining part and the printed circuit board 101 form a quarter-wavelength resonator.

It can be seen from the above description that the left open line 109 and the right open line 110 are bent towards the direction of the antenna 102 to form an L-shaped open line, so that the left open line 109 and the right open line 110 form a The choke sleeve 104 works within a certain bandwidth range to cover the entire bandwidth of the PCS (Personal Communications Service: Personal Communications Service) transmission band, which improves the truncation efficiency of the choke sleeve 104. Near the central frequency of the high-frequency band, the input impedance of the terminals of the left open line 109 and the right open line 110 is approximately infinite, and the radio frequency induced current 105 is almost completely cut off, so that the radio frequency induced current 105 cannot interfere with the hearing aid, greatly improving The HAC compatibility of the mobile phone is improved, and the radiation performance of the antenna 102 itself will not be affected.

Furthermore, as shown in Figure 3, the printed circuit board 101 is provided with a Bluetooth module 111 and a WIFI antenna module 112, and the Bluetooth module 111 and the WIFI antenna module 112 can adopt existing Any technical form will not be listed here.

The left open line 109 is configured with a left single pole double throw switch 113, the left open line 109 is connected to the active contact 114 of the left single pole double throw switch 113, and the bluetooth module 111 is connected with the bluetooth matching circuit 122 The fixed contact 115 of the left SPDT switch 113 is connected, and the fixed contact 116 of the left SPDT switch 113 is connected with the common ground 106 .

The right open line 110 is configured with a right SPDT switch 117, the right open line 110 is connected to the active contact 118 of the right SPDT switch 117, and the WIFI antenna module 112 is connected through a WIFI matching circuit 123 It is connected with the fixed contact 119 of the right single pole double throw switch 117 , and the fixed contact 121 of the right single pole double throw switch 117 is connected with the common ground 106 .

It can be seen that, through the direction connection of the left SPDT switch 113 and the right SPDT switch 117, the multiplexing of the choke sleeve 104 and the antenna 102 is realized, which is convenient for the user to switch between different function. When both the left open line 109 and the right open line 110 are connected to the common ground line 106 , the radio frequency induced current 105 can be cut off. And when described left open line 109, described right open line 110 are connected with described bluetooth module 111, described WIFI antenna module 112 respectively, mobile phone can tune described choke cover 104 to corresponding working frequency band, makes The choke sleeve 104 becomes an effective radiator, which enhances the receiving capability of the mobile phone. The technology for tuning the working frequency band of related components in the mobile phone is known in the prior art, and will not be repeated here.

Further, as shown in FIG. 3 , the printed circuit board 101 is provided with a baseband chip 120 for controlling the connection direction between the left SPDT switch 113 and the right SPDT switch 117, two SPDT switches The double-throw switches are communicatively connected with the baseband chips 120 respectively. By adjusting the connection direction of the left SPDT switch 113 and the right SPDT switch 117 through the baseband chip 120, the operation of switching different functions of the mobile phone is realized. The technology of automatic control is known in the prior art, and will not be repeated here.

The interface of the mobile phone is provided with HAC mode and normal mode, the mobile phone is in the HAC mode, and the left open line 109 and the right open line 110 are all connected to the common ground 106 to cut off the radio frequency induced current 105 , to avoid the interference noise caused by the user using the mobile phone and the hearing aid at the same time. While the mobile phone is in the normal mode, when the left open line 109 and the right open line 110 are respectively connected with the Bluetooth module 111 and the WIFI antenna module 112, the mobile phone can tune the choke cover 104 to The corresponding working frequency band makes the choke sleeve 104 an effective radiator and enhances the receiving capability of the mobile phone. The user can switch between the HAC mode and the normal mode of the mobile phone with one key, which facilitates the user's operation.

It should be understood that the above-mentioned descriptions for the preferred embodiments are relatively detailed, and should not therefore be considered as limiting the scope of the patent protection of the present invention. Within the scope of protection, various modifications such as replacement and simple combination can also be made, all of which fall within the protection scope of the present invention, and the scope of protection of the present invention should be based on the appended claims.

Claims (6)

1. mobile phone, it comprises printed circuit board (PCB), the two ends of printed circuit board (PCB) are respectively arranged with antenna and loud speaker, it is characterized in that, described printed circuit board (PCB) between described antenna and the described loud speaker is provided with the chokes cover, described chokes are set on from the radio frequency induction current path of the described loudspeaker direction conduction of alignment in described day, and described chokes cover is connected with the common ground of described printed circuit board (PCB).

2. 1 described mobile phone as requested is characterized in that, described chokes cover comprise two work in the high band centre frequency, length is the quarter-wave open-circuit line of centre frequency, it is separately positioned on the corresponding edges of boards of described printed circuit board (PCB).

3. mobile phone according to claim 2, it is characterized in that, described open-circuit line one end is connected on the described common ground, remainder is towards described printed circuit board (PCB) one end that is provided with described antenna, arrange along the length direction of the corresponding edges of boards of described printed circuit board (PCB), be provided with the gap between described remainder and the corresponding edges of boards, described remainder and described printed circuit board (PCB) form the quarter-wave resonance device.

4. mobile phone according to claim 1 and 2, it is characterized in that, described printed circuit board (PCB) is provided with bluetooth module and WIFI Anneta module, two open-circuit lines dispose single-pole double-throw switch (SPDT) respectively, open-circuit line can connect by moving contact with corresponding single-pole double-throw switch (SPDT), described bluetooth module, described common ground connect with the corresponding fixed contact of a single-pole double-throw switch (SPDT) respectively, and described WIFI module, described common ground connect with the corresponding fixed contact of another single-pole double-throw switch (SPDT) respectively.

5. mobile phone according to claim 4 is characterized in that, described printed circuit board (PCB) is provided with a baseband chip that is used to control two single-pole double-throw switch (SPDT) closures, and two single-pole double-throw switch (SPDT)s communicate to connect with described baseband chip respectively.

6. mobile phone according to claim 4 is characterized in that the layout setting of described mobile phone has HAC pattern and normal mode, and mobile phone is in described HAC pattern, and two open-circuit lines all are connected with described common ground by corresponding single-pole double-throw switch (SPDT); Mobile phone is in described normal mode, and an open-circuit line is connected with described bluetooth module by corresponding single-pole double-throw switch (SPDT), and another open-circuit line is connected with described WIFI module by corresponding single-pole double-throw switch (SPDT).

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