TWI711216B - Antenna structure - Google Patents

Abstract

The present invention provides an antenna structure, which includes a plurality of antennas and a radio frequency transceiver. The antenna includes at least one transmitting antenna and at least one receiving antenna arranged in parallel. Each antenna includes a microstrip line and two antennas arranged on both sides of the microstrip line. A plurality of antenna elements, the antenna element and the microstrip line are electrically coupled, and the antenna elements between the two antennas are arranged in a staggered manner. The radio frequency transceiver is connected to the antennas, transmits at least one transmission signal to the transmitting antenna, and receives at least one reflection signal received by the receiving antenna. Since the antenna elements are interlaced, the distance between the antenna and the antenna can be shortened, so that the overall area of the antenna is reduced without affecting the detection performance.

Description

Antenna structure

The present invention relates to an antenna structure, in particular to an antenna structure applied to radar.

According to the high-level development and application of electronic and communication technologies, automobile safety systems have become more and more popular. Among them, automobile collision avoidance radar is the application of advanced communication, control and information technology to detect vehicles, pedestrians, and road obstacles. The dynamic conditions of the surrounding objects such as the driver, such as relative position, speed, acceleration, etc., and inform the driver to take necessary measures, such as accelerating, decelerating, and keeping the lane, to prevent collisions.

Taking the current car collision avoidance radar antenna as an example, the common antenna design is a tandem rectangular patch antenna with a microstrip line architecture. As shown in Figures 1A and 1B, it is a traditional tandem patch antenna. In the schematic diagram of the antenna, since the rectangular patches 12 on a single antenna 10 are symmetrical in pairs, the rectangular patches 12 on the two microstrip lines 14 are also symmetrical to each other, and a certain distance between the two microstrip lines 14 must be maintained. As a result, it will inevitably affect the overall size of the antenna. Not only can it not be reduced in size, but the bandwidth is also narrow, such as the bandwidth of the 24GHz frequency band is about 0.5GHz. Furthermore, the antenna of Figure 1B needs to use a power divider 16 to increase signal loss.

Therefore, the present invention proposes an antenna structure to effectively solve the above-mentioned problems. The specific structure and its implementation are described in detail below:

The main purpose of the present invention is to provide an antenna structure, which uses electrical coupling to connect the microstrip line and the antenna unit to reduce the area.

Another object of the present invention is to provide an antenna structure in which the antenna elements of an array antenna and the antenna elements of adjacent array antennas are interleaved with each other, so that the distance between two adjacent array antennas can be shortened to reduce the overall area of the antenna .

Another object of the present invention is to provide an antenna structure in which the antenna elements on one side of the microstrip line and the antenna elements on the other side of the microstrip line are interlaced, so that the space between the antenna elements of an array can be inserted into the antenna elements of the adjacent array antenna. Reduce the area of the antenna.

In order to achieve the above objective, the present invention provides an antenna structure, including: multiple antennas, including at least one transmitting antenna and at least one receiving antenna, wherein each of the antennas is arranged in parallel and includes a microstrip line and a plurality of antenna elements. The antenna units are arranged on both sides of the microstrip line and are electrically coupled to the microstrip line, and the antenna units between the two antennas are arranged alternately; and a radio frequency transceiver connected to the antennas for transmission At least one transmitting signal is sent to the transmitting antenna, and at least one reflected signal received by the receiving antenna is received.

According to the embodiment of the present invention, the antenna elements in each antenna are staggered to further reduce the overall area of the antenna.

According to the embodiment of the present invention, the length and width of the antenna unit is 0.3 to 0.5 times the wavelength of the transmitted signal of the radio frequency transceiver, and the distance between two adjacent antenna units is 1.3 to 1.6 times the length and width of the antenna unit. There are staggered spaces between.

According to the embodiment of the present invention, the distance between the microstrip line and the antenna elements is less than 0.05 times the aforementioned wavelength, so that sufficient electrical coupling and connection effects can be generated between the microstrip line and the antenna elements.

The present invention provides an antenna structure, which can achieve the effects of reduced size, wider bandwidth, low loss and suitable for radar detection.

Please refer to Figure 2, which is a schematic diagram of the first embodiment of the antenna structure of the present invention. The antenna structure 10 of the present invention includes a plurality of antennas and a radio frequency transceiver 26, wherein the antennas are arranged in parallel with each other, and further includes at least one transmitting antenna 22 and at least one receiving antenna 24. In the first embodiment in FIG. 2, there are one transmitting antenna 22 and two receiving antennas 24. Each antenna 22 and 24 respectively includes a microstrip line 202 and a plurality of antenna elements 204. The antenna element 204 is a metal patch arranged on the upper and lower sides of the microstrip line 202. In the first embodiment, the antenna element 204 is They are arranged symmetrically on the upper and lower sides of the microstrip line 202, and are electrically coupled to the microstrip line 202, but not directly connected to the microstrip line 202. The radio frequency transceiver 26 is connected to the antennas 22 and 24, transmits at least one transmission signal to the transmission antenna 22, and receives at least one reflection signal received by the reception antenna 24.

In the present invention, the antenna units 204 between every two antennas are arranged in a staggered manner. The three antennas 22 and 24 in Figure 2 and the two-structure receiving antenna 24 are taken as an example. The antenna unit 204 under the receiving antenna 24 is more The upper antenna unit 204 is offset to the right, so the upper antenna unit 204 below the receiving antenna 24 can be inserted into the gap of the lower antenna unit 204 above the receiving antenna 24. In this way, the distance between the receiving antennas 24 of the two structures can be shortened. Similarly, the antenna units 204 can also be staggered between the receiving antennas 24 and the transmitting antennas 22 to further reduce the overall area of the antenna structure 20.

In the present invention, the length and width of the antenna unit 204 are 0.3 to 0.5 times the wavelength of the signal transmitted by the radio frequency transceiver. If the wavelength of the signal transmitted by the radio frequency transceiver is λ, the length and width of each antenna unit 204 is 0.3 to 0.5λ. The distance between the two adjacent antenna units 204 is 1.3 to 1.6 times the length and width of the antenna unit 204, which is larger than the antenna unit 204, so that the antenna units can be staggered. The distance between the microstrip line 202 and the antenna unit 204 is less than 0.05λ to generate an electrical coupling effect, so that the antenna unit 204 is coupled to the microstrip line 202. The line width of the microstrip line 202 is less than 0.1λ, and the distance between the two antennas is not less than 0.5λ.

The antenna structure 20 of the present invention further includes a phase converter 34, which is provided between the radio frequency transceiver 26 and the receiving antenna 24 to adjust the phase of the received reflected signal.

Each antenna 22 and 24 further includes an electrostatic protection element 28 and a DC blocker 30. The electrostatic protection element 28 is used to prevent surges from damaging the RF transceiver 26, and the DC blocker 30 can prevent human touch from being generated. Due to the current effect, when the current is too large, it will also cause damage to the RF transceiver 26, and the DC blocker 30 can avoid this situation.

Since the signal may contain a lot of noise, the transmitting antenna 22 further includes a low-pass filter 32 to filter the noise in the transmitted signal. The transmitting antenna 22 and the radio frequency transceiver 26 further include a balun 36, also called a balun, for connecting the transmitting antenna 22 and the differential signal transmitting end of the radio frequency transceiver 26.

Figure 3 is a schematic diagram of the second embodiment of the antenna structure of the present invention. In this embodiment, not only the antenna elements 204 between the two antennas 22 and 24 are interleaved with each other, but also a single antenna 22 or two upper and lower rows of antennas of the antenna 24 itself. The units 204 are also interlaced with each other. Not only can the distance between the transmitting antenna 22 and the receiving antenna 24 be further shortened, but also when there are many transmitting antennas 22 or many receiving antennas 24, the mutual distance can also be greatly shortened, as shown in As shown in Figure 4, it is a schematic diagram of an embodiment of two transmitting antennas 22 corresponding to four receiving antennas 24. It can be clearly seen that when the number of antennas increases, the upper and lower rows of antenna units 204 of the antenna itself can be staggered to reduce the required space.

The present invention only takes antenna structures such as one-transmission and two-reception, and two-transmission and four-reception as examples, but is not limited to this. Three-transmission and four-reception, and even more combinations are also within the protection scope of the present invention.

In addition, the present invention takes the design of 24GHz as an example. The wavelength of the signal transmitted by the radio frequency transceiver is about 12.5 centimeters (mm). However, this antenna structure is not limited to being used at 24GHz. Others, such as 60GHz, 77GHz... etc. Invented antenna structure.

In summary, the antenna structure provided by the present invention uses electrical coupling to connect the microstrip line and the antenna unit, so the microstrip line and the antenna unit do not need to be directly connected. In addition, in order to reduce the size of the antenna structure, the present invention further arranges the antenna elements of the upper and lower antennas alternately, and inserts the antenna element of the other antenna in the space between the two adjacent antenna elements to shorten the size of the upper and lower antennas. The distance between the strip lines, but the upper and lower rows of antenna elements of the antenna itself are symmetrical to each other. In order to further reduce the size, the present invention can also arrange the upper and lower rows of antenna elements of a single antenna in a staggered manner. Compared with the traditional antenna array, the present invention can reduce the area and increase the bandwidth, and because the wiring is short and the power divider is not required, it can reduce the loss and increase the detection range, which is quite suitable for radar detection.

Only the above are merely preferred embodiments of the present invention, and are not used to limit the scope of the present invention. Therefore, all equivalent changes or modifications made in accordance with the characteristics and spirit of the application scope of the present invention shall be included in the patent application scope of the present invention.

10: Antenna 12: Patch 14: Microstrip line 16: power divider 20: Antenna structure 202: Microstrip line 204: Antenna unit 22: Transmitting antenna 24: receiving antenna 26: RF transceiver 28: Electrostatic protection components 30: DC blocker 32: low pass filter 34: Phase converter 36: Balance converter

Figures 1A and 1B are schematic diagrams of the antenna structure in the prior art.

Figure 2 is a schematic diagram of the first embodiment of the antenna structure of the present invention.

Figure 3 is a schematic diagram of the second embodiment of the antenna structure of the present invention. Figure 4 is a schematic diagram of an embodiment of the present invention with two transmitting antennas corresponding to four receiving antennas.

20: Antenna structure

202: Microstrip line

204: Antenna unit

22: Transmitting antenna

24: receiving antenna

26: RF transceiver

28: Electrostatic protection components

30: DC blocker

32: low pass filter

34: Phase converter

36: Balance converter

Claims (9)

An antenna structure comprising: a plurality of antennas, including at least one transmitting antenna and at least one receiving antenna, wherein each of the antennas is arranged in parallel and respectively includes a microstrip line and a plurality of antenna elements, the antenna elements are arranged in the microstrip The upper and lower sides of the line are electrically coupled to the microstrip line, and the antenna elements between the two antennas are arranged in a staggered manner. The gap between the adjacent antenna elements is 1.3~ the length and width of the antenna element. 1.6 times, so that the upper antenna unit can be inserted into the gap between the lower antenna unit; and a radio frequency transceiver, which connects the antennas, transmits at least one transmission signal to the transmitting antenna, and receives what is received by the receiving antenna At least one reflected signal. The antenna structure according to claim 1, wherein the antenna elements in each antenna are arranged symmetrically or staggered up and down. The antenna structure according to claim 1, wherein the antenna unit is a metal patch, and its length and width are 0.3 to 0.5 times the wavelength of the transmitted signal of the radio frequency transceiver. The antenna structure according to claim 1, wherein the distance between the microstrip line and the antenna elements is less than 0.05 times the wavelength of the transmitted signal of the radio frequency transceiver. The antenna structure according to claim 1, wherein the line width of the microstrip line is less than 0.1 times the wavelength of the transmit signal of the radio frequency transceiver. The antenna structure according to claim 1, wherein the distance between the two antennas is not less than 0.5 times the wavelength of the transmit signal of the radio frequency transceiver. The antenna structure according to claim 1, wherein each antenna further includes an electrostatic protection element. The antenna structure according to claim 1, wherein the transmitting antenna further includes a DC barrier Device. The antenna structure according to claim 1, wherein the transmitting antenna further includes a low-pass filter.

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