Antenna system and terminal

Abstract

The embodiment of the invention discloses an antenna system and a terminal. The antenna system comprises an antenna body, an adjustable device, and a first filter and / or a second filter. The antenna body is connected with the adjustable device. The first filter is in parallel connection with the adjustable device, and the first filter has a high impedance characteristic in a low frequency band and has a low impedance characteristic in a high frequency band. The second filter is connected between the antenna body and the adjustable device in series, wherein the first end of the second filter is connected with the antenna body, the second end of the second filter is connected with the adjustable device, and the second filter has a low impedance characteristic in a low frequency band and has a high impedance characteristic in a high frequency band. Due to the arrangement of the first filter and / or the second filter, high frequency impedance is basically kept the same in the low-frequency tuning process, and the problem that high frequency impedance is involved and changes disorderly when low-frequency bandwidth tuning is conducted on the antenna system. The embodiment of the invention further discloses the terminal which comprises the antenna system.

Description

technical field [0001] The present invention relates to the field of antennas, and more specifically relates to an antenna system and a terminal. Background technique [0002] With the development and application of 4G-LTE technology, the antenna bandwidth of terminal products needs to cover more frequency bands. According to the user's demand for product portability and beautiful appearance, the space occupied by the antenna is required to be as small as possible, but miniaturization and broadband are a pair of contradictions. Therefore, under such a background, adjustable antennas become a problem to solve the contradiction. One of the trending technologies. The so-called adjustable antenna is to load different inductive and capacitive devices at the "sensitive position" of the antenna or realize the change of connection and disconnection, thereby changing the impedance characteristics of the antenna. Among them, the above-mentioned "sensitive positions" mainly include t...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, the adjustable device is used to expand the low-frequency bandwidth of the antenna. However, when the adjustable device is switched or changed, although the low-frequency operating frequency band of the antenna will change according to the expected change, each adjustable device switches or changes. Finally, or in each working state of the adjustable device, the frequency response characteristics of the antenna in the high frequency band will change accordingly, and the high frequency changes are often irregular

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