CN1972014A - Pocket super-broadband antenna - Google Patents

Abstract

A small ultra-wideband antenna is used in the technical field of wireless communication. Including: input\output port, microstrip feed unit, microstrip antenna unit, dielectric board and grounding unit. The microstrip antenna unit and the microstrip feed unit are non-uniform microstrip patches calculated according to the inverse scattering method, and are located on the front of the dielectric plate. There is one input\output port, and the input\output port is connected with the non-uniform microstrip feed unit. The ground unit is located on the opposite side of the entire dielectric board. The invention can effectively cover the frequency requirement of FCC, that is, 3.1-10.6 GHz, and is an ultra-wideband antenna with relatively small volume, simple structure and easy conformality.

Description

Small UWB Antenna

technical field

The invention relates to an antenna used in the technical field of wireless communication, in particular to a small ultra-wideband antenna.

Background technique

In recent years, ultra-wideband (UWB) short-range wireless communication has attracted great attention in the field of global communication technology. Ultra-wideband communication technology has become one of the most competitive and promising technologies for short-distance wireless communication due to its high transmission rate, strong anti-multipath interference ability, high confidentiality, and multi-functional integration. In February 2002, after the FCC released the use of UWB without a license, UWB technology quickly became a hot spot in the research and development of the international wireless communication field, and was regarded as one of the key technologies of the next generation of wireless communication. In response to the requirement of IEEE802.15.3a standard to allocate 3.1-10.6GHz frequency band for ultra-wideband communication, ultra-wide antennas have become one of the research hotspots. Some classic ultra-broadband antenna structures, such as traveling wave antenna, logarithmic periodic antenna, equiangular helical antenna, ridge waveguide horn antenna, etc., these antennas can realize the working frequency band of several octaves, and can completely cover 3.1～10.6 GHz working frequency band. However, these classic ultra-wideband antenna structures have a common disadvantage, that is, the geometric size is much larger than that of the same type of narrowband antennas, which cannot meet the requirements of a small UWB system structure. Therefore, research on the design of miniaturized ultra-wideband antennas for UWB systems is still a hot spot in antenna research in recent years.

After searching the literature of the prior art, it is found that the patent application number is 200510130662.1, the patent name is: microstrip ultra-wideband antenna, and the patent publication number is CN 1787286. The signal metal and the ground plane metal of the ultra-wideband antenna are printed on the positive side of the PCB board respectively. On the flip side, the main part of the antenna is made up of a single piece of wine glass shaped signal metal and two pieces of ground plane metal. Although the antenna can satisfy the transmission and reception of ultra-wideband pulse signals to cover the 3.1-10.6GHz working frequency band. However, the distribution of resonance points of the frequency characteristics of this antenna is not uniform, and it is difficult to achieve linear phase. In the design, it is necessary to change the size of the wine glass-shaped metal and the feeding angle to achieve the impedance matching of the antenna, which is not conducive to the miniaturization design of the antenna.

In the search, it was also found that Zhi Ning Cheng et al. proposed the anti-symmetrical Vivaldi (Vivaldi) antenna at the 2004 European Electromagnetic Conference and the Asia-Pacific Microwave Conference (APMC2005), which combines the two gradient microstrips of the two Vivaldi antennas Radiation units are designed on the front and back of the medium, and two semicircular gradient feeders are added to the feeding microstrip unit. The antenna has the characteristics of broadband impedance transformation and can effectively cover the working frequency band of 3.1-10.6GHz. However, since the gradual index line and the semicircular microstrip are used to realize the broadband characteristic, the size of the antenna is relatively large, which is not conducive to the miniaturization design of the antenna.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies and defects in the prior art, and provide a small ultra-wideband antenna, so that it can realize the requirements of the IEEE 802.15.3a standard for the 3.1-10.6GHz frequency band by using a single microstrip patch. The microstrip ultra-wideband antenna has the advantages of relatively small volume, simple structure and easy conformal shape.

The present invention is realized through the following technical solutions, and the present invention includes: input/output ports, microstrip feed unit, microstrip antenna unit, dielectric plate and grounding unit. The microstrip antenna unit and the microstrip feed unit are non-uniform microstrip line patches calculated according to the inverse scattering method. They are located on the front of the dielectric board. The core of the input/output port is connected to the microstrip feed unit. The part located on the back of the media board.

The microstrip antenna unit and the microstrip feed unit are located on the front of the dielectric plate, and the geometric dimensions of the entire antenna are calculated according to the improved Z-S inverse scattering method, and are non-uniformly distributed.

The microstrip antenna unit and the microstrip feed unit are generally composed of non-uniform microstrip patch cascades with equal electrical lengths and different widths, and their overall electrical length is based on the wavelength of 1GHz 0.2 times.

The microstrip antenna unit, the microstrip feed unit and the grounding unit are all conductors, and the grounding unit is connected to the outer conductor of the input/output port.

The dielectric plate is a material with a low dielectric constant.

The present invention is compared with the existing invention: the design of the existing ultra-wideband antenna is mainly a forward design idea, that is, the characteristics of the ultra-wideband are realized by the known structure, and the specific needs are realized by adjusting the geometric size of the antenna Antenna impedance matching improves pattern and gain. The main limitation of this design method is that the design is sometimes random and accidental, and it may be time-consuming. The advantage of this invention is that the design is a reverse design thinking process. Starting from the required index requirements, that is, the frequency characteristics, by solving the inverse problem, the impedance distribution of the antenna that can realize the frequency characteristics is solved, and then the antenna is solved. geometric distribution. The advantage of such a design method is that it has a clear goal and a fast design speed when designing the antenna. And in the design process, because the improved inverse scattering algorithm is used instead of general commercial software, the miniaturization of the antenna can be realized by continuously optimizing the objective function. The overall electrical length of the small ultra-wideband antenna of the present invention is 0.2 times the wavelength based on 1 GHz, the standing wave ratio in the designed frequency band is less than 2, and the resonance points of the frequency characteristics are evenly distributed, which can realize ultra-wideband communication The linear phase in .

The non-uniform microstrip patch antenna designed by the inverse scattering method of the present invention has relatively small size, simple structure, easy conformal shape, and effectively covers the frequency requirement of FCC, that is, the frequency band bandwidth of 3.1-10.6 GHz.

Description of drawings

Fig. 1 is the three-dimensional structure schematic diagram of a kind of small ultra-wideband antenna of the present invention

Fig. 2 is the front structure schematic diagram of a kind of small ultra-wideband antenna of the present invention

Fig. 3 is a side view structural schematic diagram of a small ultra-wideband antenna of the present invention

Fig. 4 is the reverse structure schematic diagram of a kind of small ultra-wideband antenna of the present invention

Fig. 5 is the frequency characteristic diagram of a kind of small-sized ultra-wideband antenna simulation of the present invention

Detailed ways

The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings: this embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following the described embodiment.

As shown in FIG. 1 , this embodiment includes: an input/output port 1 , a microstrip feed unit 2 , a microstrip antenna unit 4 , a dielectric board 3 and a grounding unit 5 . The microstrip antenna unit 4 and the microstrip feed unit 2 are non-uniform microstrip line patches calculated according to the inverse scattering method, located on the front of the dielectric plate 3, and the core of the input/output port 1 is in phase Then, the grounding unit 5 is the part located on the back of the dielectric board.

The microstrip antenna unit 4 and the microstrip feed unit 2 are located on the front of the dielectric plate 3, and the geometric dimensions of the entire antenna are calculated according to the improved Z-S inverse scattering method and are non-uniformly distributed. Specifically: according to the required frequency bandwidth (3.1GHz-10.6GHz), the coupling coefficient of the forward wave and the reverse wave of the non-uniform microstrip line is calculated by solving the Schrödinger equation and the Zakharov-Shabat equation group, and the coupling coefficient is solved according to the coupling coefficient The impedance distribution function of the microstrip is used to solve the geometric size distribution of the non-uniform microstrip antenna.

The microstrip antenna unit 4 and the microstrip feed unit 2 are generally composed of non-uniform microstrip patch cascades with equal electrical lengths and unequal widths, and the overall electrical length is based on 1 GHz 0.2 times the wavelength.

The microstrip antenna unit 4 , the microstrip feed unit 2 and the grounding unit 5 are all conductors, and the grounding unit 5 is connected to the outer conductor of the input/output port 1 .

The dielectric plate 3 is a material with a low dielectric constant.

As shown in FIG. 5, the frequency characteristic of this embodiment is a return loss parameter. Among them, the abscissa represents the frequency variable, and the unit is GHz; the ordinate represents the amplitude variable, and the unit is dB. The operating frequency band of a small ultra-wideband antenna in this embodiment is 2.8GHz-11.0GHz, and the return loss parameter is less than -12dB within the passband.

The working process of this embodiment is: the input/output port 1 is externally connected with a signal source, and the external excitation signal is transmitted to the microstrip antenna unit 4 through the microstrip feed unit 2, and then radiated to the surrounding space through the microstrip antenna unit 4 Go out and realize the function of wireless communication.

Claims (5)

1. A small ultra-wideband antenna, comprising: input/output port (1), microstrip feed unit (2), microstrip antenna unit (4), dielectric plate (3) and grounding unit (5), its characteristics Because: the microstrip antenna unit (4) and the microstrip feed unit (2) are non-uniform microstrip line patches calculated according to the inverse scattering method, which are located on the front of the dielectric plate (3) and are non-uniformly distributed. Input\ The core of the output port (1) is connected to the microstrip feed unit (2), and the grounding unit (5) is a part located on the back of the dielectric board (3). 2. The small ultra-wideband antenna according to claim 1, wherein the geometric dimensions of the antenna are calculated according to the improved Z-S inverse scattering method, and are distributed non-uniformly. 3. The small ultra-wideband antenna according to claim 1, characterized in that, said microstrip antenna unit (4) and microstrip feed unit (2) are as a whole made of non-uniform antennas with equal electrical lengths and unequal widths. The uniform microstrip patch is cascaded, and its overall electrical length is 0.2 times the wavelength based on 1GHz. 4. The small ultra-wideband antenna as claimed in claim 1, characterized in that, said microstrip antenna unit (4), microstrip feed unit (2) and grounding unit (5) are all conductors, and the grounding unit ( 5) Connect with the outer conductor of the input/output port (1). 5. The small ultra-wideband antenna according to claim 1, characterized in that, the dielectric plate (3) is a material with a low dielectric constant.