| 摘要 |
<p>A cradle unit for use in transmitting radiocommunication signals from within a vehicle between a portable phone unit inside a vehicle and an external antenna connected to an exterior of the vehicle is provided with a heat sink for dissipating heat generated at the cradle unit, wherein the heat sink also functions as a dipole antenna for communicating with the portable phone. In addition, the cradle unit can be provided with circuitry for charging a battery of the portable phone, along with a hands-free unit, including a speaker and microphone. The heat sink antenna allows the portable phone to receive and transmit radio frequency signals as if it were directly RF-coupled to the external antenna, thereby avoiding a 10 dB attenuation loss normally associated with using a portable phone inside a vehicle fue to the RF shielding of the metal vehicle body.</p> |
