Mobile phone

Abstract

The invention discloses a mobile phone comprising a printing circuit board of which two ends are respectively provided with antennae and a speaker. The mobile phone is characterized in that the printing circuit board between the antennae and the speaker is provided with a choke sleeve which is arranged on a radio-frequency induction current path conducting in the direction from the antennae to the speaker; and the common earth wires between the choke sleeve and the printing circuit board are connected. In the invention, the choke sleeve is arranged on the radio-frequency induction current path conducting in the direction from the antennae to the speaker; and the common earth wires between the choke sleeve and the printing circuit board are connected, which is equivalent to the condition that infinite resisters are connected on the radio-frequency induction current path in series, thus improving the HAC compatibility of the mobile phone, lowering the interfering noise caused by the mobile phone and an audiphones, and having no influence on the radiance of the antennae.

Description

technical field [0001] The invention relates to the communication field, in particular to a mobile phone compatible with hearing aids. Background technique [0002] 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 ...

AI Technical Summary

Problems solved by technology

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 ​​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 hearing aids

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

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