由於使用者對傳輸頻寬以及高速通訊服務需求的提高，一種經由多路徑傳輸方式來增加資料傳輸量的技術被稱為多輸入多輸出(Multiple-Input and Multiple-Output, MIMO)因而受到重視。本論文主要設計適用於GSM900 (890 ~ 960 MHz)、GSM1800 (1710 ~ 1880 MHz)、PCS (1850 ~ 1990 MHz)、UMTS (1920 ~ 2170 MHz)、LTE2300/2500、Zigbee、Bluetooth、WLAN (2400 ~ 2484 MHz)以及5G 802.11n等頻段之微帶線饋入式小型化槽孔式天線，此天線面積為57 × 57 mm2，主要分四個槽孔來實現多頻段的整合，其製作於FR4基板，厚度與相對介電係數分別為0.8 mm與4.4。然而，MIMO天線因以多路徑傳輸來增加容量以及傳輸距離，但同時也會增加被雜訊干擾的機率，故設計MIMO天線需考量傳遞與接收時可能發生串音干擾所帶來失真的問題。因而本論文亦探討使用微波吸收材料，並分析介電材料或磁性材料的特性，用以加強MIMO天線間的隔離，且評估減少MIMO天線串音干擾的效果，最後研究串音干擾改善是否會對天線本身的特性造成影響。

Since most users demand to have a broad bandwidth and high-speed communication service, the use of a scheme known as multiple-input and multiple-output (MIMO) is possible to multiple the data capacity of a given channel several times via using the multipath propagation that exists. This thesis mainly focuses on designing a microstrip fed slot antenna for multiband operation covering the GSM900 (890 ~ 960 MHz), GSM1800 (1710 ~ 1880 MHz), PCS (1850 ~ 1990 MHz), UMTS (1920 ~ 2170 MHz), LTE2300/2500, Zigbee, Bluetooth, WLAN (2400 ~ 2484 MHz), and the 5G 802.11n. The overall size of the designed antenna is 57 x 57 mm2, and it is printed on an FR4 substrate of thickness of 0.8 mm with dielectric constant of 4.4. Although the antennas can work simultaneously on MIMO systems that use multipath propagation to increase the capacity of the channels they use and to increase the transmission range in wireless networks, this scheme can give rise to interference that can reduce the signal to noise ratio and reduce bit error rates for digital signals. Thus, the MIMO antenna resulting from the variety of signal paths that may exist between the transmitter and receiver can cause distortion to the signal between transmitter and receiver which is known as crosstalk. This thesis also investigates the use of microwave-absorbing materials for strengthening the isolation between antennas, analyzing the characteristics of dielectric or magnetic materials on minimizing MIMO antenna crosstalk, and evaluating its performance.

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