Reversion F antenna system of four planes in use for terminals in multiple input/output communication system

Abstract

According to four quadrants, four pieces of plane reversion F antenna unit in ground plane contraction type are arranged on front face of PCB. Adjacent two pieces of antenna are perpendicular to each other with gap in 0.1-0.5 times of operation wavelength of antenna unit. Antenna units in first and third quadrants are 180+10 degrees rotational symmetry for midpoint of connecting line between same points in two pieces of antenna. Distance between feeding points are larger than 0.25 time of wavelength. Antenna units in second and fourth quadrants are in same arrangement. There is cross extension type metal ground plane with via hole connected to ground of each antenna unit. Through via hole, metal layer on back face of PCB is connected to cross extension type metal ground plane. On metal layer in backside, there is slit on blank place between units of antenna in second and third quadrants. Advantages are: small cross coupling, high radiant efficiency and large system capacity.

Description

technical field [0001] The invention relates to the field of multi-antenna antenna systems for wireless communication terminals. Background technique [0002] An antenna is a device used to radiate transmitted signal power and receive arriving signal power in a wireless communication system. Planar inverted F antenna (PIFA) is a typical built-in antenna, which consists of a conductor ground plane, a conductor radiation plane parallel to the ground plane, a conductor short-circuit column connecting the ground plane and the radiation plane, and a conductor connecting the RF feeder and the radiation plane. Conductor feeder column composition. The radiation characteristics of the PIFA antenna are mainly determined by the surface current on the metal surface of the antenna. The radiation pattern of the PIFA antenna is mainly towards the outer normal direction of the radiation plane. The main lobe width of the radiation pattern is related to the size of the ground plane, and the ...

AI Technical Summary

Problems solved by technology

For the case where the size of the antenna terminal is within 0.5 times the wavelength, the scheme where the ground planes are perpendicular to each other may not necessarily achieve high radiation efficiency, and there are problems of strong mutual coupling and low radiation efficiency

Especially for hand-held mobile terminals, the arrangement of the ground planes perpendicular to each other requires the antenna unit to be arranged on each edge of the terminal, which causes the ground current excited on the ground plane conductor to have a strong interaction with the surrounding environment, such as human hands, Due to the influence of the surrounding environment, the antenna system has the problems of unstable matching characteristics and decreased radiation efficiency

Since the battery capacity of wireless terminal equipment is usually very limited, unstable matching characteristics and a decline in radiation efficiency will significantly increase terminal power consumption and reduce standby time

[0009] On the other hand, the mutual coupling between the antenna units increases the correlation of the transmitted and received information of the coupled antenna units, which destroys the realization condition of MIMO communication, that is, the transmitted and received information of the data links where different antennas are located must have low correlation. It is also a problem existing in the application of MIMO antennas using PIFA antenna units on small-sized wireless terminals

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