CN203942027U - A kind of ultra broadband low-frequency range distortion PIFA that is applied to body area network - Google Patents

Abstract

The utility model discloses an ultra-broadband low-frequency deformed PIFA applied to a body area network, which comprises an antenna radiation unit, a floor, a feed sheet and an SMA antenna joint, wherein the antenna radiation unit includes a radiation sheet and a short circuit sheet, and the radiation sheet and the floor One end of the ground is connected by a shorting piece, the top of the feed piece is connected to the radiation piece, the bottom of the feed piece is connected to the inner conductor of the SMA antenna connector, and the other end of the floor forms a bent section. The PIFA of the utility model has the characteristics of small size, simple feeding mode, etc., and is suitable for communication of a human body area network, that is, a body area network.

Description

A UWB low-band deformable PIFA for body area network

technical field

The utility model relates to the field of body area network communication, in particular to an ultra-broadband low-frequency segment deformed PIFA applied to the body area network. the

Background technique

At present, the proposed ultra-wideband antennas for wireless body area network are relatively large in size and are easily affected by the lossy medium of the human body. Since the radiation of the planar inverted-F antenna (Planar Inverted-F Antenna, PIFA) to the human body is reduced, and the specific absorption rate is low, someone designed a planar inverted-F antenna for human body communication. However, these planar inverted-F antennas have complex structures and are difficult to manufacture. the

Generally speaking, planar inverted-F antennas can be classified as monopole antennas. Figure 1, Figure 2, and Figure 3 respectively show the evolution of three types of monopole antennas to planar inverted-F antennas: the first is to wire monopole After bending, add an inverted L-shaped conductive wire to the left side to realize a plane inverted F structure. Finally, the bent conductive wire can be extended to a plane to increase the frequency band of the antenna; the second is a microstrip antenna, which is bent and placed on Add conductive wire grounding on the same side of the feed line to realize the planar inverted F structure; the third is to load the monopole sub-wire antenna on the top plate, and add conductive plane grounding on the top plate side to realize the planar inverted F structure. During the design process, adding a short circuit to the left end of the antenna is equivalent to introducing an inductance into the parallel resonant circuit formed by the antenna to offset the capacitance introduced by the bending of the monopole antenna on the right side. the

Utility model content

The purpose of the utility model is to overcome the shortcomings and deficiencies of the prior art, and provide an ultra-broadband low-frequency deformed PIFA applied to the body area network, and its size is small. the

The purpose of this utility model is realized through the following technical solutions:

An ultra-wideband low-frequency deformed PIFA applied to body area networks, including an antenna radiating unit, a floor, a feeder and an SMA (Sub-Miniature-A) antenna connector, wherein the antenna radiating unit includes a radiator and a short circuit, and the radiator One end of the ground is connected with a short-circuit piece, the top of the feed piece is connected with the radiation piece, the bottom of the feed piece is connected with the inner conductor of the SMA antenna connector, and the other end of the floor forms a bent section. the

The shape of the radiation sheet is a right-angled trapezoid, the length L _t1 of the upper bottom is 7 mm, the length L _t2 of the lower bottom is 3 mm, and the length L of the waist is 13 mm.

The height h of the short-circuit sheet is 5.5 mm to 6 mm, and the width w _s is 5 mm; the width w _f of the feed sheet is 7 mm; the distance h _f between the bottom of the feed sheet and the floor is 1 mm; the short-circuit sheet and the feed The distance d between the sheets is 5 mm; the length L _g of the floor is 60 mm, the width W _g is 22 mm, the height h _g of the bent section of the floor is 7 mm, and the length L _c is 17 mm. When the height h of the short circuit is 5.5mm, with S ₁₁ ≤ -10dB as the standard, the antenna covers the 1.5GHz frequency band (3.5～5GHz); and when h is 6mm, the antenna covers the bandwidth of 3.1～4.9GHz, a total of 1.7GHz frequency band; Although continuing to increase h, the antenna bandwidth increases slightly, but setting h to 6mm can cover the required frequency band. The distance d between the shorting sheet and the feeding sheet affects the depth of the antenna reflection coefficient. After optimization, if d is selected as 5mm, the antenna can cover the required 3.1-4.9GHz frequency band.

Compared with the prior art, the utility model has the following advantages and beneficial effects:

1. The utility model adopts the hypotenuse top plate technology to realize impedance matching, and further widen the frequency band, and then adopts the bent floor method to make the antenna well cover the ultra-wideband low frequency band of 3.1-4.9 GHz. the

2. After the utility model adopts the hypotenuse roof technology and the folding floor, the planar inverted F antenna covers 3.1-4.6GHz in free space and 3.4-4.6GHz on the human body (reflection coefficient S ₁₁ ≤-10dB). Due to the influence of the human body, the performance of the antenna on the human body is slightly worse than the free space performance, but still acceptable, making this planar inverted-F antenna suitable for use in body area network systems.

3. The utility model considers the loss of the substrate material, the air with a dielectric constant ε _r = 1 and an electrical loss angle tanδ≈0 is used as the medium between the roof radiation patch and the floor, and the air gap can also be used for installation Other electronic equipment; the antenna feed piece is coplanar with the floor and there is a certain feed port between the two, so the inner conductor of the SMA connector is directly welded to the feed piece, and the outer conductor is connected to the floor by welding, so avoid Solved the problem of drilling holes in the floor.

Description of drawings

Figure 1 is a schematic diagram of the evolution of the first monopole antenna;

Figure 2 is a schematic diagram of the evolution of the second monopole antenna;

Figure 3 is a schematic diagram of the evolution of the third monopole antenna;

Fig. 4 is a structural schematic diagram of the ultra-broadband low-band deformation PIFA applied to the body area network described in the present invention;

Fig. 5 is the partially enlarged view of the dotted circle encircled part of deformed PIFA described in Fig. 4;

FIG. 6 is a schematic diagram of dimension parameters of the deformed PIFA shown in FIG. 4 . the

Detailed ways

The utility model will be further described in detail below in conjunction with the embodiments and accompanying drawings, but the implementation of the utility model is not limited thereto. the

As shown in Figures 4 and 5, an ultra-wideband low-frequency deformed PIFA applied to body area networks includes an antenna radiation unit, a floor 1, a feeder 2 and an SMA antenna connector 4, wherein the antenna radiation unit includes a radiation unit 5 and a short circuit 6. One end of the radiation sheet 5 and the floor 1 is connected through a short circuit sheet 6, the top of the feed sheet 2 is connected to the radiation sheet 5, the bottom of the feed sheet 2 is connected to the inner conductor 3 of the SMA antenna connector 4, and the other end of the floor 1 forms Bending section 7, the bending section 7 is bent upwards from the other end of the floor 1 and bent to the left; wherein the SMA antenna connector 4 is connected to the coaxial cable to output the signal received by the PIFA;

As shown in Figure 6, the shape of the radiation sheet is a right-angled trapezoid, the length L _t1 of the upper bottom is 7 mm, the length L _t2 of the lower bottom is 3 mm, and the length L of the waist is 13 mm;

As shown in Figure 6, the height h of the short-circuit sheet is 5.5mm to 6mm, and the width w _s is 5mm; the width w _f of the feed sheet is 7mm; the distance h _f between the bottom of the feed sheet and the floor is 1mm; The distance d between the sheet and the feed sheet is 5mm; the length L _g of the floor is 60mm, the width W _g is 22mm, the height h _g of the bent section of the floor is 7mm, and the length L _c is 17mm. When the height h of the short circuit is 5.5mm, with S ₁₁ ≤ -10dB as the standard, the antenna covers the 1.5GHz frequency band (3.5～5GHz); and when h is 6mm, the antenna covers the bandwidth of 3.1～4.9GHz, a total of 1.7GHz frequency band; Although continuing to increase h, the antenna bandwidth increases slightly, but setting h to 6mm can cover the required frequency band.

The above-mentioned embodiment is a preferred implementation mode of the present utility model, but the implementation mode of the present utility model is not limited by the above-mentioned embodiment, and any other changes, modifications and substitutions made without departing from the spirit and principle of the present utility model , combination, and simplification, all should be equivalent replacement methods, and are all included in the protection scope of the present utility model. the

Claims (3)

1. A kind of deformation PIFA of ultra-broadband low frequency band that is applied to body area network, it is characterized in that: comprise antenna radiating unit, floor, feed sheet and SMA antenna connector, wherein antenna radiating unit comprises radiating sheet and short circuit sheet, radiating sheet and One end of the floor is connected through a short circuit, the top of the feed sheet is connected to the radiation sheet, the bottom of the feed sheet is connected to the inner conductor of the SMA antenna connector, and the other end of the floor forms a bent section. the 2. The ultra-wideband low-frequency deformation PIFA applied to body area network according to claim 1, characterized in that: the shape of the radiation sheet is a right-angled trapezoid, the length _L of the upper bottom is 7mm, and the length of the lower bottom is L _t2 is 3 mm, and the waist length L is 13 mm. 3. The ultra-broadband low-frequency deformed PIFA applied to body area network according to claim 1, characterized in that: the height h of the short circuit piece is 5.5 mm to 6 mm, and the width w _s is 5 mm; The width w _f is 7mm; the distance h _f between the bottom of the feed sheet and the floor is 1mm; the distance d between the short circuit sheet and the feed sheet is 5mm; the length L _g of the floor is 60mm, and the width W _g is 22mm. The height h _g of the bent section is 7 mm, and the length L _c is 17 mm.