阅读说明：本技术 螺旋段天线 (Helical segment antenna ) 是由 塞德里克·马泰尔 杰罗米·马西奥特 奥利维厄·帕斯卡尔 娜撒莉·拉沃 于 2019-09-06 设计创作，主要内容包括：一种发射来自沿着引导路径传播的至少一个电磁行波的辐射的天线(100)设计成减少很可能在所述引导路径末端处发生的所述行波的反射。为此目的,所述引导路径具有呈螺旋段(11、12)形式的至少一个部分,所述至少一个部分连接到所述引导路径的呈环圈(13)形式的另一部分。可以此方式获得所述天线的反射系数增益,所述增益在所述天线的传输频带的下限频率限值附近尤其有效。(An antenna (100) emitting radiation from at least one electromagnetic travelling wave propagating along a guide path is designed to reduce reflections of the travelling wave likely to occur at the ends of the guide path. For this purpose, the guide path has at least one section in the form of a spiral section (11, 12) which is connected to another section of the guide path in the form of a loop (13). The reflection coefficient gain of the antenna, which is particularly effective around the lower frequency limit of the transmission band of the antenna, can be obtained in this way.)

1. An antenna (100) for emitting radiation from at least one travelling electromagnetic wave, which propagates along a guide path determined by the structure of the antenna, the guide path forming a transmission line dedicated to the travelling wave and having at least one path portion in the form of a spiral section (11, 12) extending to a terminating end of the spiral section,

the guide path additionally comprising a continuous loop (13) surrounding each helical segment (11, 12), and the terminating end of each helical segment being connected to the loop at the connection point (PR1, PR2) of the helical segment, such that an electrical signal transmitted to a feed input (E) of the antenna (100) produces a travelling wave propagating along each helical segment, which travelling wave is then transmitted to the loop at the connection point of the helical segment,

characterized in that, for each spiral segment (11, 12), the antenna (100) further comprises a bridging structure (SP1, SP2) arranged for connecting the spiral segment to the loop (13) upstream of the connection point (PR1, PR2) with respect to the propagation direction of the travelling wave along the spiral segment for the purpose of transporting the travelling wave and in addition to the connection point,

and wherein, for the helical section (11, 12), the two lengths of the guiding path between the bridging structure (SP1, SP2) and the connection point (PR1, PR2), measured respectively along the helical section and along the loop (13), are each equal to one quarter of the same effective wavelength value of the travelling wave, within +/-20%, corresponding to the frequency value belonging to the transmission band of the antenna (100).

2. The antenna (100) of claim 1, wherein each helical segment (11, 12) is tangentially connected to the loop (13) at the connection point (PR1, PR2) of the helical segment.

3. The antenna (100) according to claim 1 or 2, characterized in that the effective wavelength of the travelling wave acting as a reference between the bridging structure (SP1, SP2) and the connection point (PR1, PR2) respectively along the length of the helical segment and the guiding path measured along the loop (13) is between 0.75/n times and 1.25/n times the length of the loop, n being a positive integer.

4. The antenna (100) according to any of the preceding claims, characterized in that the bridge structure (SP1, SP2) has an impedance value that is between 1 and 3 times a characteristic impedance value of the helical segment (11, 12) and the loop (13) that are common outside of respective intermediate portions (11i, 12i, 13i) of the helical segment and the loop, the respective intermediate portions being between the bridge structure (SP1, SP2) and the connection point (PR1, PR2), the impedance value and the characteristic impedance value of the bridge structure being effective for the travelling wave.

5. The antenna (100) of claim 4, wherein the helical segments (11, 12) and the intermediate portion (11i, 12i, 13i) of the loop (13) have respective characteristic impedance values that are each between 0.5 x 2 of the characteristic impedance value common to the helical segments and the loop outside the intermediate portion^1/2Multiple and 1.5X 2^1/2Between multiples.

6. The antenna (100) according to any of the preceding claims, structured to define several identical guide path portions each in the form of a spiral segment (11, 12) and extending to a terminating end, wherein the spiral segments are connected to the loop (13) separately from other spiral segments,

and the antenna (100) is configured such that all guiding path portions in the form of helical segments (11, 12) transmit respective travelling waves to the loop (13) simultaneously.

7. The antenna (100) of claim 6, wherein each helical segment (11, 12) is connected to the loop (13) by a respective bridging structure (SP1, SP2) separately from each other helical segment, and each helical segment with a corresponding bridging structure reproduces the features of any one of claims 1 to 5 independently of each other helical segment.

8. The antenna (100) according to any of the preceding claims, having a slot antenna configuration formed in the first metal surface (10).

9. The antenna (100) according to claim 8, further comprising a second metal surface (20) parallel to the first metal surface (10), electrically insulated from the first metal surface and arranged in the vicinity of the first metal surface such that the radiation is limitedly emitted by the antenna by an emission direction oriented from the second metal surface towards the first metal surface.