This paper presents an LTE MIMO closed slot antenna system for laptops with a metal cover. Its main and auxiliary antennas have the same structure that measures 130 × 3 mm 2. They are configured in a manner of reflection symmetry on the display metallic ground plane and are 5 mm away from the hinge. The distance between the two antennas is 20 mm, and the profile height of the MIMO antenna system is only 3 mm. This LTE closed slot antenna is excited by an exciter of 30 × 3 mm 2 to cover the LTE eight-band operation (LTE700/GSM850/900/1800/1900/UMTS/LTE2300/2500). The exciter is a simple planar inverted-F antenna (PIFA) structure loaded with reactive matching elements, which can enhance the impedance matching in the desired frequency bands. This LTE MIMO closed slot antenna system has good isolation of at least 16 dB without adding any additional isolation elements. The measured antenna efficiency of the MIMO antenna system is larger than 40% in the low-frequency band and 50% in the high-frequency band, meeting the practical application requirements. INDEX TERMS Laptop antennas, closed slot antennas, LTE MIMO antennas, ECC (envelope correlation coefficient). I. INTRODUCTION With the popularity of the fourth-generation (4G) mobile communication long-term evolution (LTE) technology and the demand for fast wireless transmission rates, multipleinput multiple-output (MIMO) systems have been widely used in many mobile communication devices to respond to today's massive data transmission. In addition, thin portable smart phones, tablets, or laptops with a fashionable appearance of a metal cover and a high screen-to-body ratio are a trend-setting mobile communication device. However, the large screen-to-body ratio, metal back cover, and slim appearance restrict the space allowed for antenna design. On the basis of the above conditions, it is a serious challenge for antenna researchers to configure in an internal-space-limited metal-cover mobile communication device an LTE MIMO antenna system with high isolation. High transmission speed, light weight, thin appearance, and fashionable metal texture of the cover are the features that most consumers require nowadays when choosing mobile The associate editor coordinating the review of this manuscript and approving it for publication was Mohammad Tariqul Islam.

No abstract

No abstract