Radio-frequency transceiver system

#1. Field of the Invention

#The present invention relates to a radio-frequency transceiver system, and more particularly, to a radio-frequency transceiver system capable of solving asynchronous signal problems and field pattern shielding problems.

#2. Description of the Prior Art

#FIG. 1A is a schematic diagram illustrating a radio-frequency transceiver system according to an embodiment of the present invention.

#FIG. 1B is a schematic diagram illustrating a top view of the radio-frequency transceiver system shown in FIG. 1A.

#FIG. 2 is a schematic diagram illustrating antenna resonance simulation results of the radio-frequency transceiver system shown in FIG. 1A.

#Please refer to FIG. 1A and FIG. 1B. FIG. 1A is a schematic diagram illustrating a radio-frequency transceiver system 10 according to an embodiment of the present invention. FIG. 1B is a schematic diagram illustrating a top view of the radio-frequency transceiver system 10. The radio-frequency transceiver system 10 can be disposed in a cylindrical radome RAD and comprises a signal processing module (not shown), a first complex antenna ANT1 and a second complex antenna ANT2. The first complex antenna ANT1 and the second complex antenna ANT2 support 2×2 multiple-input multiple-output (MIMO) communication technology, respectively. A switching circuit (not shown) of the signal processing module manipulates the first complex antenna ANT1 and the second complex antenna ANT2 according to signal transmission directions. In this way, the first complex antenna ANT1 and the second complex antenna ANT2 provide two independent antenna transmission and reception channels respectively, and the radio-frequency transceiver system 10 can serve as a 4×4 MIMO beam switching cantenna. The first complex antenna ANT1 and the second complex antenna ANT2 comprise first antenna units A1U1, A1U2, A1U3, A1U4 and second antenna units A2U1, A2U2, A2U3, A2U4 respectively. As shown in FIG. 1B, the first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4 are regularly and alternately arranged to form an annular structure. Namely, each of the first antenna units is adjacently disposed between two of the second antenna units, and each of the second antenna units is adjacently disposed between two of the first antenna units. For example, the first antenna unit A1U1 is disposed between the second antenna units A2U1 and A2U4. By switching on or turning off the first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4, the switching circuit can switch the first complex antenna ANT1 and the second complex antenna ANT2 between a single-beam mode and a combined-beam mode so as to correctly transmit/receive radio-frequency signals. In the combined-beam mode, field patterns (or radiation patterns) of antenna units adjacent to each other (e.g., the second antenna units A2U1 and A2U4) of the second complex antenna ANT2 or the first complex antenna ANT1 can be synthesized into a composite field pattern in order to compensate for an attenuation of gain value of each individual single-beam field pattern of the adjacent antenna units (i.e., the second antenna units A2U1 and A2U4) near their intersection (e.g., the intersection plane PL1), thereby enhancing overall gain value.

#In short, the first complex antenna ANT1 and the second complex antenna ANT2 share one signal processing module, and the signal processing module integrally processes signals transmitted from or received by the first complex antenna ANT1 and the second complex antenna ANT2. Therefore, problems of synchronization failure of signals transmitted between the first complex antenna ANT1 and a baseband radio processor (not shown) of the signal processing module and between the second complex antenna ANT2 and the baseband radio processor can be prevented. Because the first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4 are regularly and alternately arranged to form an annular structure, the size of the radio-frequency transceiver system 10 can be smaller without shielding individual single-beam field pattern of each of the first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4. The first complex antenna ANT1 and the second complex antenna ANT2 are disposed in the cylindrical radome RAD completely to solve asynchronous signal problems and to reduce cost. Besides, when the first complex antenna ANT1 is switched to the single-beam mode, the second complex antenna ANT2 can be switched to the combined-beam mode; similarly, when the first complex antenna ANT1 is switched to the combined-beam mode, the second complex antenna ANT2 can be switched to the single-beam mode. In such a situation, when corresponding to the same spatial position, the envelope correlation coefficient (ECC) between the first complex antenna ANT1 and the second complex antenna ANT2 is lowered down, thereby enhancing performance of 4×4 MIMO communication technology applications of the radio-frequency transceiver system 10.

#Specifically, the first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4 comprise reflective plates 120a_A1U1 to 120b_A1U4, 120a_A2U1 to 120b_A2U4, radiation units 141a_A1U1 to 142b_A1U4, 141a_A2U1 to 142b_A2U4, supporting elements 160a_A1U1 to 160b_A1U4, 160a_A2U1 to 160b_A2U4 and reflective units 190_A1U1 to 190_A2U4 respectively. The first antenna units A1U1 to A1U4 and the second antenna units A2U1 to A2U4 are identical and have the same structure and size so as to divide the cylindrical radome RAD up into 8 equal sections each having the same space angle. Beam overlapping patterns of the first complex antenna ANT1 and the second complex antenna ANT2 therefore have identical shape and the same magnitude and are evenly distributed to cover 360 degrees in the horizontal plane (i.e., the xz plane). However, the beam overlapping pattern of the first complex antenna ANT1 was tilted 45 degrees relative to the beam overlapping pattern of the second complex antenna ANT2 owing to the misalignment of the first complex antenna ANT1 and the second complex antenna ANT2. In other words, a projection of the radio-frequency transceiver system 10 orthogonally projected onto the horizontal plane is symmetrical with respect to 8 symmetrical axes. For the sake of brevity, details about the radio-frequency transceiver system 10 are described by focusing merely on the first antenna unit A1U1 and the second antenna unit A2U1. The reflective unit 190_A1U1 of the first antenna unit A1U1 and the reflective unit 190_A2U1 of the second antenna unit A2U1 comprise peripheral reflective elements 191_A1U1 to 194_A1U1, 191_A2U1 to 194_A2U1 and central reflective elements 195_A1U1, 195_A2U1 respectively. Each of the peripheral reflective elements 191_A1U1 to 194_A1U1 has a shape substantially conforming to an isosceles trapezoid with symmetry. Taken together, the peripheral reflective elements 191_A1U1 to 194_A1U1 enclose the central reflective element 195_A1U1 symmetrically to form a frustum structure. Similarly, each of the peripheral reflective elements 191_A2U1 to 194_A2U1 has a shape substantially conforming to an isosceles trapezoid with symmetry, and the peripheral reflective elements 191_A2U1 to 194_A2U1 enclose the central reflective element 195_A2U1 symmetrically to form a frustum structure. Here, each central reflective element (for example, the central reflective element 195_A1U1) of the first antenna units (for example, the first antenna unit A1U1) of the first complex antenna ANT1 and each central reflective element (for example, the central reflective element 195_A2U1) of the second antenna units (for example, the second antenna unit A2U1) of the second complex antenna ANT2 are perpendicular to a first plane (i.e., the horizontal plane), and hence the projection of the radio-frequency transceiver system 10 onto the first plane is symmetrical with respect to at least one symmetrical axis.