CN111509385A

CN111509385A - Intelligent watch antenna

Info

Publication number: CN111509385A
Application number: CN202010348157.9A
Authority: CN
Inventors: 赵鲁豫; 刘洋
Original assignee: Xi'an Longpuda Communication Technology Co ltd
Current assignee: Xi'an Longpuda Communication Technology Co ltd
Priority date: 2020-04-28
Filing date: 2020-04-28
Publication date: 2020-08-07

Abstract

The invention discloses an intelligent watch antenna, which comprises a dielectric substrate, a main antenna structure on the front surface of the dielectric substrate and a metal floor layer on the back surface of the dielectric substrate, wherein the main antenna structure comprises a main antenna and a diversity antenna, the main antenna and the diversity antenna are respectively an eighth circular metal patch, short circuit nails are respectively arranged on the main antenna and the diversity antenna close to the right edge of the antennas, and annular gaps are respectively arranged in the middle areas of the two antennas.

Description

Intelligent watch antenna

Technical Field

The invention relates to a miniaturized intelligent terminal antenna, in particular to an intelligent watch antenna.

Background

With the slowing of the increase of the global smart phone industry, the continuous increase of the industry competition and the lack of continuous innovation capability, the mobile phone industry has met the development bottleneck. All big mobile terminal manufacturers such as apple, samsung and hua, chip huge heads such as high pass, linkage department and platform developers and scheme providers represented by google are actively exploring the next category which has the opportunity to stimulate the growth of the intelligent mobile terminal industry, and the mobile phone-based intelligent mobile terminal can have strong enough use viscosity, is very portable and has strong practicability. In many emerging industries such as virtual reality, artificial intelligence, internet of things, 5G and intelligent wearing, wearable products basically have the above features and have a large development space, and one important development direction is towards enhancing convenience and practicability independent of a mobile phone.

In recent years, intelligent wearable products are continuously developing and evolving, and more practical application scenes such as children's conversation positioning watches, motion detection and reminding, sleep detection and improvement suggestions, acquisition and analysis through a large amount of human body data, and continuous attempts in the health field are emerging. With apple intelligent wrist-watch and millet intelligent bracelet as the representative, the wearable industry of whole intelligence is gradually returning rationality, and practicality, fashion and possess more connection function.

The communication function of the current smart watch for children is mainly realized by one or more technologies such as Bluetooth WiFi, NFC (near field communication), GPS (Global positioning System), 2G, 3G, L TE, and the like, wherein Bluetooth, NFC, GPS (near field communication), 2G, 3G, L TE and the like are selected in the text,

The WiFi, GPS, L TE and NFC relatively representative antennas are researched, through the design and optimization of the miniaturized antenna, on the premise that the passive parameter requirement of the antenna is met, the requirements of the appearance, the structure and the size of a product can be met, and meanwhile, the electromagnetic radiation injury to children cannot be caused.

Objectively limited by physical size, antenna performance, especially in the low frequency band (below 1 GHz) is a difficult point in current industry design.

Aiming at the platform of the intelligent watch terminal, due to the limited geometric dimension and the complex structural form of the antenna, the frequency band requirements of general products are basically to cover not only the frequency bands of GSM850 (0.82-0.89 GHz), GSM900 (0.88-0.96 GHz), DCS1800 (1.71-1.88 GHz), PCS1900 (1.85-1.99 GHz) and UMTS (1.9-2.17 GHz) required by 3G and 4G, but also the frequency bands of L TE700 (0.69-0.78 GHz), L TE2300 (2.3-2.4 GHz) and L TE2500 (2.5-2.69 GHz) newly proposed by 5G.

The design space of the antenna is also greatly limited and the electromagnetic environment around the antenna becomes extremely complex, which also greatly increases the design difficulty of the antenna. Designing an antenna capable of covering multiple frequency bands or a wide frequency band in a limited space under the condition of ensuring that the performance is not influenced is a main challenge of designing a watch antenna at present. To achieve coverage of multiple bands or a wide band of the antenna.

Compared with a microstrip patch antenna with a common structure, the microstrip patch antenna with the microstrip loop antenna has the characteristics of low profile, low loss, easiness in conformal and easiness in manufacturing, has the physical characteristics of compact and simple structure and the like, and most importantly, has better multimode characteristic. At present, microstrip loop antennas are widely used in the research of circular polarization, omnidirectional and multi-frequency antennas. In the research of the multi-frequency antenna, a combination of 2 low-order modes of a circular loop antenna and a multi-patch loop antenna is generally used to realize the multi-frequency characteristic.

Disclosure of Invention

The invention provides an intelligent watch antenna, which utilizes the 3 rd mode of a microstrip circular antenna to realize the multi-frequency characteristic of the antenna. It is proposed and realized to control these modes by adding slot and shorting pin structures so that the antenna operates in a desired frequency band.

The technical scheme of the invention is as follows:

an intelligent watch antenna comprises a dielectric substrate, a main antenna structure on the front surface of the dielectric substrate, and a metal floor layer on the back surface of the dielectric substrate; the main antenna structure comprises a main antenna and a diversity antenna, wherein the main antenna and the diversity antenna are one-eighth circular ring metal patches, and circular ring center lines of the two antennas are mutually vertical; the main antenna and the diversity antenna are respectively provided with a short-circuit nail at the edge close to the right side of the antenna, and the two antennas are respectively connected with the metal floor layer through the holes on the dielectric plate by adopting the short-circuit nails.

Preferably, the central regions of the main antenna and the diversity antenna are respectively provided with a first annular slot and a second annular slot.

Preferably, the first annular gap and the second annular gap are concentric with the annular metal patch of the antenna.

Preferably, a first feeder line and a second feeder line are respectively arranged at the proximal ends of the metal patches of the main antenna and the diversity antenna, and the two feeder lines adopt coaxial feeding or microstrip coupling feeding.

Preferably, the medium base plate is made of FR4 plate, the thickness of the medium base plate is 0.8mm, and the whole medium base plate is circular with the diameter of 40 mm.

The invention has the advantages that:

1. the invention adopts two microstrip loop antennas of a main antenna and a diversity antenna, the working frequency bands of the antennas are L TEband13 (747-787 MHz), B5 and B9 (824-960 MHz) and L TEband1 (1980-2170 MHz), and the MIMO diversity technology is supported.

2. The two antennas are vertically arranged and are in orthogonal polarization, and the isolation degree is good.

3. An annular gap is formed in the antenna metal patch, the electrical length of each mode current is prolonged, so that each frequency point is reduced, and the antenna is more sensitive to the gap.

4. After the short-circuit pin is added to the right edge of the patch, the patch is equivalent to an electric wall, so that correspondingly, the frequency is reduced to half of the original frequency, an eighth-loop antenna can excite 3 frequency modes by adding the short-circuit pin, and the frequency points are controlled by the slot, so that the antenna works at the required frequency.

Drawings

The invention is further described with reference to the following figures and examples:

FIG. 1 is a schematic diagram of a smart watch antenna according to the present invention;

fig. 2 is a diagram of parameters S of the smart watch antenna of the present invention after the addition of both a loop gap and a short staple.

Detailed Description

The design of the antenna is based on a certain intelligent watch, the working frequency bands of the antenna are L TEband13 (747 + 787 MHz), B5 and B9 (824 + 960 MHz) and L TEband1 (1980 + 2170 MHz), and the antenna supports the MIMO diversity technology and needs two antennas.

As shown in fig. 1, the smart watch antenna of the present embodiment includes a dielectric substrate, a main antenna structure on the front surface of the dielectric substrate, and a metal floor layer 8 on the back surface of the dielectric substrate. The dielectric substrate was made of FR4, and had a dielectric constant of 4.4, a tangent loss angle of 0.02, a thickness of 0.8mm, and a circular shape with an overall dimension of 40mm in diameter.

The main antenna structure comprises a main antenna 1 and a diversity antenna 2, wherein the main antenna 1 and the diversity antenna 2 are one-eighth circular ring metal patches, circular ring center lines of the two antennas are perpendicular to each other, orthogonal polarization is formed, and good isolation is achieved.

Main antenna 1 and diversity antenna 2 set up short-circuit peg 7 respectively near antenna right side edge, and two antennas adopt short-circuit peg 7 to connect metal floor layer 8 through the hole on the dielectric plate respectively. The middle areas of the main antenna 1 and the diversity antenna 2 are respectively provided with a first annular gap 5 and a second annular gap 6, and the first annular gap 5 and the second annular gap 6 are respectively concentric with the circular metal patch of the antenna.

The proximity ends of the metal patches of the main antenna 1 and the diversity antenna 2 are respectively provided with a first feeder line 3 and a second feeder line 4, and the two feeder lines adopt coaxial feeding or microstrip coupling feeding.

The annular gap extends the electrical length of each mode current, thereby reducing each frequency point. Furthermore, the antenna is more slot sensitive. When the shorting pin 7 is added to the right edge of the patch, it acts as an electrical wall, so correspondingly, the frequency is reduced to half of the original. An eighth-loop antenna can excite 3 frequency modes by adding a short-circuit pin, and controls the frequency points by slotting so as to enable the antenna to work at the required frequency.

Fig. 2 is a diagram showing the parameters of the antenna S after the addition of the annular slot and the shorting pin. The one-eighth three-ring antenna can work well at 0.7GHz,1.8GHz and 2.4 GHz. When the short-circuit nail is removed, the simulation and actual measurement results of the eighth-loop antenna cannot meet the required multi-frequency characteristics. Further simulation and actual measurement results show that: when the short-circuit nail is removed, the original eighth ring is changed into the quarter ring, and the size of the gap is properly changed, the obtained quarter-ring antenna can still work at the required 3 frequency points, so that the effect of the short-circuit nail is further reflected.

The simulation result of fig. 2 shows that the designed antenna has a wider bandwidth, good radiation omnidirectionality and higher radiation efficiency, and completely meets the requirements of the intelligent watch on actual work.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose of the embodiments is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All modifications made according to the spirit of the main technical scheme of the invention are covered in the protection scope of the invention.

Claims

1. An intelligent watch antenna is characterized by comprising a dielectric substrate, a main antenna structure on the front surface of the dielectric substrate, and a metal floor layer (8) on the back surface of the dielectric substrate; the main antenna structure comprises a main antenna (1) and a diversity antenna (2), wherein the main antenna (1) and the diversity antenna (2) are both one-eighth circular ring metal patches, and circular ring center lines of the two antennas are mutually vertical; the main antenna (1) and the diversity antenna (2) are respectively provided with a short-circuit nail (7) at the edge close to the right side of the antenna, and the two antennas are respectively connected with a metal floor layer (8) through holes on a dielectric plate by adopting the short-circuit nails (7).

2. Smart watch antenna according to claim 1, characterised in that the central areas of the main antenna (1) and the diversity antenna (2) are opened with a first annular slot (5) and a second annular slot (6), respectively.

3. A smart watch antenna according to claim 2, characterised in that the first annular slot (5) and the second annular slot (6) are respectively concentric with the annular metal patch of the antenna in which they are located.

4. A smart watch antenna according to claim 2, characterised in that the proximal ends of the metal patches of the main antenna (1) and the diversity antenna (2) are provided with a first feed line (3) and a second feed line (4), respectively, both feed lines being fed by coaxial feed or microstrip coupling.

5. A smart watch antenna as claimed in claim 2, wherein the dielectric substrate is made of FR4 board material, and has a thickness of 0.8mm and an overall circular shape with a diameter of 40 mm.