| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a waterproof foldable mobile telephone capable of reducing echo generated on the correspondent terminal when a hands-free call is performed with the telephone in a folded state. <P>SOLUTION: A foldable mobile telephone includes: a first housing having a receiver and a speaker, with a receiver hole and speaker hole blocked by a waterproof film; and a second housing having a microphone, with a microphone hole blocked by a waterproof film, and the waterproof film blocking the receiver hole and the waterproof film blocking the microphone hole face each other when the telephone is folded. Further, the mobile telephone includes: a low-pass filter that is connected to an output side of the microphone and whose cutoff frequency is 1 kHz; and an echo canceller that is connected to an output side of the low-pass filter and remove, from an output signal of the low-pass filter, a component of an input signal to the speaker. <P>COPYRIGHT: (C)2012,JPO&INPIT |
