| 摘要 |
<p>PROBLEM TO BE SOLVED: To effectively use a frequency resource in consideration of difference in communication systems and their operation frequency bands at the outside and at the inside.SOLUTION: A conversion device 10 comprises: a wireless modem 20 which receives a radio signal of a first communication system operated with a first frequency band from the outside, and converts the received radio signal into a signal based on an Internet protocol; and a femtocell base station 30 which converts the signal based on the Internet protocol into a radio signal of a second communication system operated with a second frequency band, and transmits the converted radio signal to the inside.</p> |
