Communication device and communication method

1 . A communication device, comprising:

a first FSS (Frequency Selective Surface) element;

a second FSS element, disposed adjacent to the first FSS element;

a feeding radiation element, generating an electromagnetic signal, wherein the electromagnetic signal is propagated by using the first FSS element and the second FSS element; and

at least one DLA (Dielectric Laser Accelerator), transmitting at least one electron beam;

wherein an antenna structure is formed by the first FSS element, the second FSS element, and the feeding radiation element;

wherein a coupling effect is induced between the electron beam and the electromagnetic signal, such that radiation energy of the electromagnetic signal is enhanced.

2 . The communication device as claimed in claim 1 , wherein the first FSS element is configured to partially reflect and partially transmit the electromagnetic signal.

3 . The communication device as claimed in claim 1 , wherein the second FSS element is configured to completely reflect the electromagnetic signal.

4 . The communication device as claimed in claim 1 , wherein the second FSS element is made of an AMC (Artificial Magnetic Conductor) material.

5 . The communication device as claimed in claim 1 , wherein the second FSS element is made of a metal material.

6 . The communication device as claimed in claim 1 , wherein the DLA is disposed between the first FSS element and the second FSS element.

7 . The communication device as claimed in claim 1 , wherein the antenna structure covers an operational frequency band from 60 GHz to 500 GHz.

8 . The communication device as claimed in claim 7 , wherein a specific distance between the first FSS element and the second FSS element is substantially equal to 0.25 wavelength of the operational frequency band.

9 . The communication device as claimed in claim 7 , wherein a specific distance between the first FSS element and the second FSS element is substantially equal to 0.5 wavelength of the operational frequency band.

10 . The communication device as claimed in claim 1 , further comprising:

a plurality of DLAs, transmitting a plurality of electron beams.

11 . The communication device as claimed in claim 10 , wherein the electron beams have a same transmission direction.

12 . The communication device as claimed in claim 10 , wherein the electron beams have different transmission directions.

13 . The communication device as claimed in claim 10 , wherein the DLAs are arranged to form an array.

14 . The communication device as claimed in claim 10 , wherein the DLAs are arranged along a loop.

15 . The communication device as claimed in claim 14 , wherein the loop substantially has a circular shape or an elliptical shape.

16 . The communication device as claimed in claim 1 , further comprising:

a metal waveguide, disposed below the second FSS element.

17 . A communication method, comprising the steps of:

generating an electromagnetic signal by a feeding radiation element;

using a first FSS (Frequency Selective Surface) element and a second FSS element to propagate the electromagnetic wave, wherein the second FSS element is disposed adjacent to the first FSS element, and wherein an antenna structure is formed by the first FSS element, the second FSS element, and the feeding radiation element; and

transmitting at least one electron beam by at least one DLA, wherein a coupling effect is induced between the electron beam and the electromagnetic signal, such that radiation energy of the electromagnetic signal is enhanced.

18 . The communication method as claimed in claim 17 , further comprising:

transmitting a plurality of electron beams by a plurality of DLAs.

19 . The communication method as claimed in claim 18 , further comprising:

arranging the DLAs to form an array.

20 . The communication method as claimed in claim 18 , further comprising:

arranging the DLAs along a loop.