TWI271004B - Low-cost coaxial cable fed type inverted-L antenna - Google Patents

Abstract

The present invention provides a low-cost coaxial cable fed type inverted-L antenna. The dipole antenna uses a coaxial cable to extend an internal conductor, which is contained in the dipole antenna, outwards along the axial direction for a preset length from one end of the internal conductor to beyond an external conductor, which is also contained in the dipole antenna, before extending backwards along the direction in adjacent and parallel with the external conductor for another preset length to form a radiating unit. Since neither other component nor soldering process is required in the whole antenna structure, not only the manufacturing and process costs can be lowered and the production variations can be minimized significantly for achieving a higher production yield rate but also the assembly time and process can be shortened effectively for achieving a higher production efficiency.

Description

1271004

TECHNICAL FIELD OF THE INVENTION The present invention is a low-cost coaxial cable feed type inverted antenna, especially a dipole antenna made of a coaxial cable. Prior Art: A type of dipole antenna 2 used in a conventional wireless communication device 1, as shown in Fig. 1, is generally a coaxial cable sleeve type dipole antenna (see Figure 2) As shown, the dipole antenna 2 includes a coaxial cable 10 that includes an inner conductor 14 (or a mandrel) and an outer conductor 16 (or a shield mesh or a ground wire). The inner conductor 14 Separated from the outer conductor 16 by an insulating dielectric material 17 to form the inner conductor 14 and the outer conductor 16 of the shaft - electromagnetically referred to as the same body. In addition, the coaxial cable ίο The outer edge is covered with an insulating sheath 19, and the straight end is connected to the control circuit of the wireless communication device (not shown), and the other end is sleeved with a metal sleeve 18, and the metal sleeve is externally The conductor 16 is coaxial, and the metal sleeve 18 has only the upper end μ and the outer conductor 26 is connected. The rest of the metal sleeve 18 is separated from the outer conductor 16 by the 19 The outer conductor 16 is connected to the inner conductor 14 and extends from the other end of the coaxial cable 1 by a length β, and the length thereof is about The length of the metal sleeve 18, but both of which are: one quarter of the wavelength of the frequency (1/4 ί, 丨 represents the wavelength of the operating frequency), such that the metal sleeve 18 and the outer conductor 16 will form another / a ~ conductor, can be used to prevent the external conductor 16 outside the leakage current generated by the radiation 1271004 ·

The radiated interference ' constitutes a balanced to unbalanced converter (balun) that causes the same-axis cable-type dipole antenna to produce the desired antenna radiation. In general, in a mobile or portable wireless communication device, such as the mobile phone commonly used today, an omnidirectional radiation field type antenna must be installed to maintain the wireless communication device at 36 degrees. Azimuth, communication, and the aforementioned dipole antenna is the most commonly selected antenna on the wireless communication device, and the dipole antenna is commonly used to receive or transmit high frequency ( In the wireless communication device of the frequency band signals such as HF), ultra-high frequency (VHF) and ultra-high frequency (UHF), the basic structure mainly uses the metal sleeve 18 on the coaxial cable sleeve type dipole antenna. Set a balanced-to-unbalanced converter (Balun). In addition, in order to increase the gain of the antenna line to maintain the omnidirectional radiation pattern, the coaxial linear structure (Col linear) is generally used to design the species. Coaxial cable sleeve dipole antenna. Because the IEEE 8〇211 Wireless Local Area Network (Wireless Locai Area Netw〇rk) protocol, which was enacted in 1977, not only provides many unprecedented functions in wireless communication, but also provides wireless for various types of cards. The product has been able to communicate with each other. Therefore, the agreement has opened up a new milestone for the development of the communication line, and the market demand for mobile communication products has increased, making the development of wireless communication faster. Therefore, in recent years' Many wireless communication products are designed and manufactured by manufacturers who are ready to develop wireless communication devices that can receive or transmit frequency signals such as Southern Frequency (HF), Ultra High Frequency (VHF) and Very High Frequency (uhf). An antenna that is simple in structure, easy to assemble, and inexpensive to manufacture. When the antenna is used in such wireless communication products, it can effectively reduce the occupation of the antenna.

Page 6 1271004 V. Description of invention (3). However, the high-band antennas currently seen on the market, in addition to the aforementioned conventional coaxial wound-sleeve dipole antennas (s丨eeveantenna), there are also manufacturers using the knowledge i: with the antenna (printedante η na) production technology Designing and manufacturing an equivalent dipole antenna 2, as shown in FIG. 3, the antenna 2 includes a flat dielectric material 2 〇, the dielectric substrate 20 before and after On the side, a first microstrip line 22 and a second microstrip line 24 are respectively printed, wherein the first microstrip line 22 printed on the front side is used as a signal transmission line, and one end thereof is used as a signal feeding end 21, The inner conductor 3 1 (or the mandrel) of the coaxial line 30 is connected to a control circuit of a wireless communication device (not shown), and the other end of the first microstrip line 22 is The corresponding side extends an appropriate length of the radiator 25, the length of the radiator 25 is slightly shorter than a quarter of the wavelength of the operating frequency (ie, 1/4 丨, 丨 represents the wavelength of the operating frequency), and the dielectric The second material on the back side of the base material 2 The microstrip line 24 is printed in a shape corresponding to the signal feeding end 21 of the first microstrip line 22 on the front side, and the second microstrip line is "the microstrip line 241 located at the middle portion. The coaxial cable (3) (or shield mesh or ground wire) can be connected to the ground terminal (not shown) on the control circuit of the wireless communication device through the coaxial cable 3 () outer conductor (not shown) The line m eats the microstrip line 241@ in the middle portion, and the tail current of the microstrip line 242 on the two sides of the other concentric conductor forms a balance to unbalanced converter (balun).哕 ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ Or the traditional coaxial cable-sleeve dipole antenna, although the characteristics can meet the requirements, but the traditional dipole antenna is too large, or the structure is too complicated, such as · · = dipole antenna Need to connect the upper end of the metal sleeve === body phase to the microstrip antenna, Another design and production of a printing ink =: anti-day f 'and assembled in the temple, the artificial coaxial cable and the printed circuit board antenna are welded together, not only increase the production, processing and assembly of the installation space is unnecessary Waste, material, due to the microwave frequency = short wavelength, in the welding process for manufacturing these dipole antennas, the vana i on is relatively high, which easily leads to a decrease in production yield. In view of the fact that the technology of manufacturing in the south and lower yields has carefully studied various inverted antennas that have been developed and designed. One of the inner conductors of the present invention, which is adjacent to an outer conductor, is attached to the radiator of the length of the outer conductor, The cost of the dipole antenna is missing. After the improvement, the line feed-in cable will be returned to the other, and there is no such thing as a conventional antenna, which is large in size and complicated in structure. Based on years of experience and accumulated professional knowledge, aiming at the above solution, and continuously researching, experimenting and presenting a low-cost coaxial electric winding of the present invention, it is only necessary to benefit A coaxial electric body extends from the other end and, after being extended for a predetermined length, is reversely bent and parallel to the direction of the outer conductor, extending to form the entire antenna structure of the present invention. The piece 'does not need to be connected to other processing procedures,

1271004

It can reduce the production and processing cost of the antenna, reduce the production ease, and improve the production yield. It can effectively simplify the assembly time and procedures and improve the efficiency of manufacturing. Another purpose of this month is that the total length of the radiator is only about a quarter of the wavelength of the operating frequency, and the length is longer than the conventional micro-antenna or coaxial cable-type dipole antenna. The length can be shortened by nearly half. Therefore, the miniaturized dipole antenna of the present invention can effectively reduce the size of the wireless overnight product, so that it conforms to the trend of thin and light design. A further understanding and understanding of the shape, structure, design, and efficacy of the present invention will be provided for the member of the singapore. Here are a few examples, and the drawings are described in detail as follows: Embodiment: In the present invention A preferred embodiment of the dipole antenna includes an inner conductor 44 (or a mandrel) and a concentric conductor between the inner conductor 44 and the outer conductor μ for the coaxial cable 4 to be referred to therein. Further, the outer skin 4 9 ' is connected at one end thereof (not shown), the inner guide is controlled along the axial direction thereof, and the inner conductor 44 is controlled to the side by the predetermined length.

In an embodiment, referring to FIG. 4, the coaxial cable 40 includes an outer conductor 46 (or a shield mesh or a ground wire), which is insulated by a dielectric material 47. Separatingly, the conductor 44 and the outer conductor 46 form an electromagnetically. The outer edge of the coaxial cable 40 is covered with an insulation to a wireless communication device. The upper body 44 is connected to the other end of the coaxial winding 4'. Outside of 4 6 , a predetermined length is extended outwardly. The position of the resonant frequency of the dipole antenna is bent at about 90 degrees and extends another predetermined length.

Page 9 1271004 V. Inventive Note (6), then, adjacent to the outer conductor 46 and parallel to the outer conductor 46, f is folded by about 90 degrees, and continues to extend another radiator of a predetermined length, The radiator 50 is slightly shorter than the wavelength of the operating frequency (i.e., 1/4 1 I represents the wavelength of the operating frequency), and the radiator 5 is adjacent to the body 4, and is external to the The distance between the conductors 46 is maintained at an appropriate distance. Thus, by appropriately controlling the distance between the radiator 50 and the outer conductor 46, it is possible to properly match between the inner conductor 44 and the outer conductor 46. The concentric conductor can be used to prevent the f-radiation generated by the leakage current outside the outer conductor 46, and constitute a balanced to unbalanced converter (balun), such as the expected radiation of the coaxial cable-casing dipole antenna effect. In the preferred embodiment, the reference to Fig. 4 is repeated, and it is required to note that the dipole antenna of the present invention is proved by the experimental test; the distance from the coaxial cable 40 is required to be accompanied. It has a better high frequency effect at °.保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持 保持Bending back in the opposite direction, extending beyond and parallel to the direction of the outer conductor 46, extending: 4 out of the length of the outer conductor 46 (1/4 i represents the slightly frequency frequency of the operating frequency The two bodies 50' and the radiation body 5. and the coaxial cable 4 between the two 'forming the dipole antenna of the present invention, leaving the line operating in the band of 22 to 2.7 billion Hz (GHz) 'measured back ^The Return Loss, the measurement result is shown in Figure 5 dB 'so the 'planar omnidirectional ^ field designed by the invention ^

1271004 V. Description of invention

The line does achieve excellent antenna gain in the designed operating band. According to the foregoing embodiments of the present invention, the dipole antenna of the present invention requires only one coaxial cable to easily complete the structural design of the entire antenna, without any additional components, and no other processing procedures such as welding. Therefore, not only can the production and processing cost of the antenna be greatly reduced, the flexibility in production can be reduced, the production yield can be improved, the working hours and procedures of assembly can be simplified, and the efficiency of manufacturing can be improved. In addition, since the total length of the radiator 50 of the dipole antenna of the present invention is only about one quarter of the operating frequency wavelength, the length is shorter than that of the conventional microstrip antenna or the coaxial cable sleeve dipole antenna. With nearly half the length, the dipole antenna of the small plasticized design of the present invention can effectively reduce the volume of the wireless communication product, so that it conforms to the trend of light and thin design. The above is only the preferred embodiment of the present invention, but the scope of the claimed invention is not limited thereto, and the technical content disclosed in the present invention can be easily obtained by those skilled in the art. Equivalent changes in thought should be made without departing from the scope of the invention.

1271004 Schematic diagram of the simple description: Figure 1 is a schematic diagram of a conventional conventional wireless communication device; Figure 2 is a schematic diagram of a conventional coaxial cable-sleeve dipole antenna; Figure 3 is a conventional microstrip dipole antenna 4 is a schematic diagram of a dipole antenna according to a preferred embodiment of the present invention; and 5 is a result of actual measurement of the return loss according to the dipole antenna provided in FIG. The main part of the symbol:

Coaxial cable...............40 W inner conductor..................44 outer conductor....... ............46 Insulation Dielectric Material.....47 Insulation Skin...............49 Radiator.......... .........50

Page 12

Claims (1)

1271004 VI. Patent application scope 1. A low-cost coaxial cable feed-in inverted L antenna includes a coaxial cable, the coaxial cable comprising: an inner conductor, a mandrel of the coaxial cable, As a wireless signal transmission line; an outer conductor is used as a shielding and grounding wire; an insulating dielectric material is disposed between the inner conductor and the outer conductor, and is separated by a distance between the inner conductor and the outer conductor Forming a concentric conductor; an insulating sheath covering the outer edge of the outer conductor; wherein one end of the coaxial cable is connected to a control t-circuit of a wireless communication device, and the inner guiding system is further One end extends and extends beyond the outer conductor for a predetermined length, and then reversely bends back, extending another radiator of a predetermined length in a direction adjacent to the outer conductor and parallel to the outer conductor. 2. The antenna of claim 1, wherein the inner conductor extends from the other end of the coaxial cable to the predetermined length, and can be bent to about one side by about 90 degrees to extend another predetermined schedule. length. 3. The antenna of claim 2, wherein the inner conductor extends beyond the further predetermined length and is further bent about 90 degrees toward the outer conductor and parallel to the outer conductor. And continuing to extend the radiator of the other predetermined length. 4. The antenna of claim 1, wherein the distance between the radiator and the coaxial cable is maintained between about 2 mm and 8 mm. 5. The antenna of claim 1, 2 or 3, wherein the antenna Page 13 1271004 Page 14