Precise tuning system for broadband antenna

Abstract

The invention discloses a precise tuning system for a broadband antenna, which comprises a PIFA antenna, a tuner, a tuning component and a filter, and is characterized in that the PIFA antenna comprises a radiator, a first pin and a second pin, the first pin and the second pin are arranged on the lower end wall of the front end part of the radiator side by side, the lower end part of the first pin is provided with a grounding point, and the lower end part of the second pin is provided with a second grounding point; the lower end part of the second pin is provided with a feed point, the feed point is electrically connected with the radio frequency front end through a feed line, one end of each tuner is electrically connected with the lower end part of the first pin or the feed line, the number of the filters is one or more, the filters are arranged at the lower end parts of the tuners, and the filters and the tuners are connected in parallel. The tuning components are connected with the filters in series and electrically connected with the ground. According to the technical scheme provided by the invention, different frequency bands can be accurately tuned by matching different filters without influencing other frequency bands, and meanwhile, additional resonance caused by inherent Ron and Coff of a radio frequency tuning switch can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a precise tuning system for broadband antennas. Background Art

[0002] Antenna efficiency plays a critical role in the overall RF performance of automotive communications and smartphones. However, current automotive communications and smartphone industrial design trends and RF requirements (especially the upcoming transition to 5G) mean that automotive communications and smartphones must fit more antennas into a smaller space and / or increase the bandwidth of existing antennas.

[0003] The design of the RF front end (RFFE) of modern in-vehicle communications and smartphones is becoming increasingly complex due to the increasing number of frequency bands, functions and modes required for in-vehicle communications and smartphones to operate. The number of antennas in in-vehicle communications and smartphones has increased from 4-6 to 8 or more due to the need to use more antennas, carrier aggregation (CA), 4x4 MIMO, Wi-Fi MIMO and new wideband 5G bands to provide higher data rates. At the same time, the space available for mobile system antennas has shrunk, resulting in reduced antenna efficiency.

[0004] Some of the lost performance can be recovered through antenna tuning. Without tuning, the antenna may perform well over a limited frequency range, but adding antenna tuning can achieve more optimized performance over a wider frequency range.

[0005] Antenna tuning systems, such as impedance tuners and aperture tuners, can support the higher bandwidth and carrier aggregation required by LTE in-vehicle communications and smartphones. They enable antennas to operate efficiently across the entire LTE and 5G frequency bands (from 600 MHz to 5Ghz), while also saving battery power and enabling miniaturized in-vehicle communications and smartphone designs.

[0006] Commonly used antenna tuning systems include impedance tuners and aperture tuners, but they both have two obvious problems: 1. Tuners have a tuning effect on all frequency bands and cannot tune certain specific frequency bands separately; for example: the antenna system hopes to tune the low frequency band (697MHz~960MHz), but in the actual tuning process, the high frequency band (such as 1710MHz~2690MHz) is also tuned, resulting in undesirable tuning effects and increasing the difficulty of debugging; 2. RON and COFF bring unnecessary resonance; two key characteristics of the aperture tuning switch will significantly affect the efficiency of the antenna: on-state resistance (RON) and off-state capacitance (COFF). The aperture switch is a capacitive switch in the off state (COFF) and a resistive switch in the on state (RON). If the inductor is connected to the RF port for tuning, the combination of COFF and the inductor will produce unnecessary resonance. Summary of the invention

[0007] The main purpose of the present invention is to propose a precise tuning system for broadband antennas, aiming to solve the problems mentioned in the above background technology. By matching different filters, different frequency bands can be precisely tuned respectively without affecting other frequency bands, while solving the unnecessary resonance caused by Ron and Coff.

[0008] To achieve the above-mentioned purpose, the present invention proposes a precise tuning system for a broadband antenna, including a PIFA antenna, a tuner, a tuning component and a filter. The PIFA antenna includes a radiator, a first pin and a second pin. The first pin and the second pin are arranged side by side on the lower end wall of the front end of the radiator. A grounding point is provided at the lower end of the first pin, and a feeding point is provided at the lower end of the second pin. The feeding point is electrically connected to the RF front end through a feeder. One end of the tuner is electrically connected to the lower end of the first pin or the feeder. One or more filters are provided, and the filter is arranged at the lower end of the tuner. The filter and the tuner are connected in parallel. The tuning components are respectively connected in series with the filters, and the tuning components are respectively electrically connected to the ground.

[0009] Optionally, the tuner is an aperture tuner, which is disposed at a lower end of the first pin, one end of the aperture tuner is electrically connected to the first pin, and the other end of the aperture tuner is electrically connected to the filter.

[0010] Optionally, the tuner is an impedance tuner, which is disposed at the lower end of the second pin, one end of the impedance tuner is electrically connected to the feeder, and the other end of the impedance tuner is electrically connected to the filter.

[0011] Optionally, the characteristic frequencies of the filters are different from each other.

[0012] Optionally, the filter is a low-pass filter, a high-pass filter, a band-pass filter, or a band-stop filter.

[0013] Optionally, the filter is an LC filter, a SAW filter, a BAW filter, or a ceramic filter.

[0014] The technical solution of the present invention has the following beneficial effects: the technical solution of the present invention is that the first pin and the second pin are arranged side by side on the lower end wall of the front end of the radiator, the lower end of the first pin is provided with a grounding point, the lower end of the second pin is provided with a feeding point, the feeding point is electrically connected to the RF front end through a feeder, one end of the tuner is electrically connected to the lower end of the first pin or the feeder, one or more filters are provided, the filter is arranged at the lower end of the tuner, the filter and the tuner are connected in parallel, the tuning components are respectively connected in series with the filters, the tuning components are respectively electrically connected to the earth, and the filter is added between the antenna\antenna feeder and the tuning component The array is designed by inserting a tuning architecture of a filter array corresponding to the tuning frequency band between the antenna\antenna feeder and the tuning components. Through the frequency selection characteristics of the filter, the tuning components only tune the antenna within the filter passband frequency, and the filter stopband frequency range is not affected. By matching different filters, different frequency bands can be accurately tuned respectively without affecting other frequency bands, and unnecessary resonance caused by Ron and Coff can be solved, so that the antenna can be accurately tuned within the filter frequency band without affecting other frequency bands, and the additional resonance caused by the inherent Ron and Coff of the RF tuning switch can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0016] Figure 1 This is a schematic diagram of the overall structure of a precise tuning system for a broadband antenna according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of a precise tuning system for a broadband antenna according to another embodiment of the present invention; Figure 3 A tuning effect diagram of an existing antenna tuning system; Figure 4This is a tuning effect diagram of a precise tuning system for a broadband antenna according to an embodiment of the present invention.

[0017] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0020] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0021] The present invention provides a precise tuning system for a broadband antenna.

[0022] like Figures 1 to 4 As shown, in one embodiment of the present invention, the precise tuning system for broadband antenna includes a PIFA antenna 100, a tuner 200, a tuning component 300 and a filter 400. The PIFA antenna 100 includes a radiator 101, a first pin 102 and a second pin 103. The first pin 102 and the second pin 103 are arranged side by side on the lower end wall of the front end of the radiator 101. The lower end of the first pin 102 is provided with a grounding point, and the lower end of the second pin 103 is provided with a feeding point. The feeding point is electrically connected to the RF front end through a feeder 104. One end of the tuner 200 is electrically connected to the lower end of the first pin 102 or the feeder 104. One or more filters 400 are provided. The filter 400 is arranged at the lower end of the tuner 200. The filter 400 and the tuner 200 are connected in parallel. The tuning components 300 are respectively connected in series with the filters 400, and the tuning components 300 are respectively electrically connected to the ground.

[0023] Specifically, the tuner 200 is an aperture tuner, which is disposed at the lower end of the first pin 102 , one end of the aperture tuner is electrically connected to the first pin 102 , and the other end of the aperture tuner is electrically connected to the filter 400 .

[0024] Specifically, the tuner 200 is an impedance tuner, which is disposed at the lower end of the second pin 103 , one end of the impedance tuner is electrically connected to the feed line 104 , and the other end of the impedance tuner is electrically connected to the filter 400 .

[0025] Specifically, the characteristic frequencies of the filter 400 are different from each other, and the tuning components only tune the antenna within the filter passband frequency, and the filter stopband frequency range is not affected. By matching different filters, different frequency bands can be accurately tuned without affecting other frequency bands, and at the same time, unnecessary resonance caused by Ron and Coff can be solved.

[0026] Specifically, the type of the filter 400 is a low-pass filter, a high-pass filter, a band-pass filter, or a band-stop filter.

[0027] Specifically, the filter 400 is an LC filter, a SAW filter, a BAW filter, or a ceramic filter.

[0028] Specifically, the present invention can achieve precise tuning of the antenna within the filter frequency band without affecting other frequency bands by adding a filter array between the antenna, the antenna feeder and the tuning components; at the same time, it can avoid the additional resonance caused by the inherent Ron and Coff of the RF tuning switch, and the tuning effect is as follows: Figure 4 shown.

[0029] Specifically, compared Figure 3 and Figure 4 The present invention has the following advantages: 1. Through the frequency selection characteristics of the filter, the tuning components only tune the antenna within the filter passband frequency, and the filter stopband frequency range is not affected; 2. The frequency selection characteristics of the filter can eliminate additional resonant frequencies in the out-of-band frequency range.

[0030] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A precision tuning system for a broadband antenna, characterized in that: The invention comprises a PIFA antenna, a tuner, a tuning component and a filter. The PIFA antenna comprises a radiator, a first pin and a second pin. The first pin and the second pin are arranged side by side on the lower end wall of the front end of the radiator. A grounding point is arranged at the lower end of the first pin. A feeding point is arranged at the lower end of the second pin. The feeding point is electrically connected to a radio frequency front end through a feeder. One end of the tuner is electrically connected to the lower end of the first pin or the feeder. One or more filters are arranged at the lower end of the tuner. The filter and the tuner are connected in parallel. The tuning components are respectively connected in series with the filters, and the tuning components are respectively electrically connected to the earth.

2. The precise tuning system for broadband antenna according to claim 1, characterized in that: The tuner is an aperture tuner, which is disposed at the lower end of the first pin, one end of the aperture tuner is electrically connected to the first pin, and the other end of the aperture tuner is electrically connected to the filter.

3. The precise tuning system for broadband antenna according to claim 1, characterized in that: The tuner is an impedance tuner, which is arranged at the lower end of the second pin, one end of the impedance tuner is electrically connected to the feeder, and the other end of the impedance tuner is electrically connected to the filter.

4. The precise tuning system for broadband antenna according to claim 1, characterized in that: The characteristic frequencies of the filters are different from each other.

5. The precise tuning system for broadband antenna according to claim 1, characterized in that: The type of the filter is a low-pass filter, a high-pass filter, a band-pass filter, or a band-stop filter.

6. The precise tuning system for broadband antenna according to claim 1, characterized in that: The filter is an LC filter, a SAW filter, a BAW filter or a ceramic filter.

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