Summary: | 碩士 === 臺灣大學 === 電子工程學研究所 === 98 === Currently, wireless local area network (Wireless LAN) and Bluetooth are two important standards in the wireless communication network. They are broadly used and are irreplaceable. However, IEEE 802.11g in Wireless LAN and Bluetooth both utilize 2.4 GHz ISM band. Mutual interference occurs while the two systems modulate signals to the same spectrum at the same time. This is so-called the ISM coexistence issue. The general solution is to avoid simultaneous system operation in the time or frequency domain. By doing this, the throughput and spectral efficiency are sacrificed for the collision avoidance. Therefore, joint detection is proposed as a better solution to jointly detect Wi-Fi and Bluetooth in order to reduce the interference.
Maximum likelihood is applied in joint detection to search all possible Wi-Fi and Bluetooth signal through a built-in Bluetooth library. As the most likely Bluetooth is found, it is subtracted from the received signal to reduce the interference. The simulation results under different simulation environments: with perfect channel state information (CSI) knowledge and considering the real coexistence environment are proposed to show the effectiveness of the joint detector dealing with ISM coexistence.
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