Dual-band plastic waveguide transmission system

Abstract

According to the present disclosure, a dual-band plastic waveguide transmission system is provided. The system may include an RF receiver configured to receive a first signal and a second signal, the first and second signals being transmitted from an RF transmitter at a first carrier frequency and a second carrier frequency higher than the first carrier frequency, respectively; a plastic waveguide device configured to provide a communication channel between the RF transmitter and the RF receiver; and an interconnect device including a first microstrip-to-waveguide transition (MWT) configured to transmit the first signal from the plastic waveguide device to the RF receiver and a second MWT configured to transmit the second signal from the plastic waveguide device to the RF receiver. The frequency bandwidth of the first signal may be adjusted by the plastic waveguide device and the first MWT so that the first signal is received as an upper sideband signal, and the frequency bandwidth of the second signal may be adjusted by the plastic waveguide device and the second MWT so that the second signal is received as a lower sideband signal.

Description

[Technical Field]

[0001] The present disclosure relates to waveguide links, and more particularly to dual-band plastic waveguide transmission systems. [Background technology]

[0002] The demand for greater input / output (I / O) bandwidth in data sensors is increasing due to the explosive growth of network traffic. However, traditional high-speed interconnects face functional and economic challenges. Copper-based electrical links exhibit critical bandwidth limitations caused by skin loss. Optical links require chip-to-fiber assembly in short-reach, high-capacity links and significant capital expenditures for E / O (Electrical / Optical) and O / E conversion devices.

[0003] As an alternative to solving the problems of conventional high-speed interconnects, recent research has shown that plastic waveguide links, which exhibit inherent low-loss and wide-bandwidth channel characteristics, could be a promising solution for providing power- and cost-effective high-speed interconnects. Accordingly, there is a need to develop transmission systems that enable ultra-high-speed data transmission through plastic waveguide links. Summary of the Invention [Problem to be solved by the invention]

[0004] To solve these problems, the present disclosure aims to provide a dual-band plastic waveguide transmission system. [Means for solving the problem]

[0005] According to one embodiment of the present disclosure, a dual-band plastic waveguide transmission system is provided. The system includes an RF receiver configured to receive a first signal and a second signal transmitted from an RF transmitter at a first carrier frequency and a second carrier frequency higher than the first carrier frequency, respectively; a plastic waveguide device configured to provide a communication channel between the RF transmitter and the RF receiver; and an interconnect device including a first microstrip-to-waveguide transition (MWT) configured to transmit the first signal from the plastic waveguide device to the RF receiver and a second MWT configured to transmit the second signal from the plastic waveguide device to the RF receiver. The frequency bandwidth of the first signal can be adjusted by the plastic waveguide device and the first MWT so that the first signal is received as an upper sideband signal, and the frequency bandwidth of the second signal can be adjusted by the plastic waveguide device and the second MWT so that the second signal is received as a lower sideband signal.

[0006] The system may further include a duplexer coupled to the first MWT and the second MWT, respectively, for transmitting the first signal and the second signal from the plastic waveguide device.

[0007] In addition, the frequency bandwidth of the first signal can be adjusted by adjusting a lower cut-off frequency of the plastic waveguide device, and the frequency bandwidth of the second signal can be adjusted by adjusting an upper cut-off frequency of the plastic waveguide device.

[0008] The plastic waveguide device may also include a dielectric tube having a rectangular cross section, and the lower cutoff frequency of the first signal and the upper cutoff frequency of the second signal may be adjusted based on the horizontal and vertical lengths of the cross section of the dielectric tube.

[0009] Furthermore, the frequency bandwidth of the first signal can be adjusted by adjusting an upper cutoff frequency by the first MWT, and the frequency bandwidth of the second signal can be adjusted by adjusting a lower cutoff frequency by the second MWT.

[0010] Each of the first MWT and the second MWT may include a probe element that receives a signal from a feeding line; and a slotted ground plane through which the signal radiated from the probe element passes and is transmitted to the plastic waveguide device.

[0011] Additionally, the upper cutoff frequency of the first signal may be adjusted based on the length of the probe element of the first MWT and the slot size of the slotted ground plane of the first MWT, and the lower cutoff frequency of the second signal may be adjusted based on the length of the probe element of the second MWT and the slot size of the slotted ground plane of the second MWT.

[0012] The RF receiver may be additionally configured to receive a third signal and a fourth signal transmitted from the RF transmitter at a third carrier frequency lower than the first carrier frequency and a fourth carrier frequency higher than the second carrier frequency, respectively. The interconnection device may further include a third MWT configured to transmit the third signal from the plastic waveguide device to the RF receiver; and a fourth MWT configured to transmit the fourth signal from the plastic waveguide device to the RF receiver. The frequency bandwidth of the third signal may be adjusted by the plastic waveguide device and the third MWT so that the third signal is received as an upper sideband signal, and the frequency bandwidth of the fourth signal may be adjusted by the plastic waveguide device and the fourth MWT so that the fourth signal is received as a lower sideband signal.

[0013] Additionally, the system may further include a quadplexer for transmitting the first signal, the second signal, the third signal, and the fourth signal from the plastic waveguide device.

[0014] Furthermore, the frequency bandwidth of the first signal and the frequency bandwidth of the third signal can be adjusted by adjusting the lower cutoff frequency of the plastic waveguide device, and the frequency bandwidth of the second signal and the frequency bandwidth of the fourth signal can be adjusted by adjusting the upper cutoff frequency of the plastic waveguide device.

[0015] Furthermore, the frequency bandwidth of the first signal can be adjusted by adjusting the upper cutoff frequency by the first MWT, the frequency bandwidth of the second signal can be adjusted by adjusting the lower cutoff frequency by the second MWT, the frequency bandwidth of the third signal can be adjusted by adjusting the upper cutoff frequency by the third MWT, and the frequency bandwidth of the fourth signal can be adjusted by adjusting the lower cutoff frequency by the fourth MWT. [Effects of the Invention]

[0016] According to the present disclosure, a transmission system can be provided that enables ultra-high speed data transmission by adjusting the frequency bandwidth of dual-band or multi-band RF signals for single-sideband transmission and transmitting and receiving them through a plastic waveguide link. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is an exemplary diagram illustrating single sideband transmission.

[0018] [Figure 2] 1 is an exemplary diagram illustrating a dual-band plastic waveguide transmission system according to one embodiment of the present disclosure.

[0019] [Figure 3] 1 is an exemplary plot showing lower and upper cutoff frequencies of a plastic waveguide channel response.

[0020] [Figure 4] 1 is an exemplary diagram illustrating a configuration of a plastic waveguide device according to an embodiment of the present disclosure.

[0021] [Figure 5] 1 is an exemplary diagram illustrating a cross-sectional view of a package substrate including an MWT according to one embodiment of the present disclosure.

[0022] [Figure 6a] 6 is an exemplary diagram showing a slotted ground plane in the A-A' plane of FIG. 5;

[0023] [Figure 6b] 6 is an exemplary diagram showing a probe element located on the BB' plane of FIG. 5;

[0024] [Figure 7] 1 is an exemplary diagram illustrating a multi-band plastic waveguide transmission system according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, when assigning reference numerals to components in each drawing, it should be noted that the same reference numerals are used to designate the same components even when they are displayed in different drawings. Furthermore, when describing the present invention, detailed descriptions of related known structures or functions will be omitted if it is determined that such descriptions may obscure the gist of the present invention.

[0026] Various aspects of the present invention are described below. It should be understood that the inventions presented herein may be embodied in a variety of forms, and that any specific structure, function, or all of these presented herein are merely exemplary. Based on the inventions presented herein, a person of ordinary skill in the art to which the invention pertains will understand that one aspect presented herein may be embodied independently of any other aspect, and that two or more such aspects may be combined in various ways. For example, a device may be embodied or a method may be practiced using any number of the aspects described herein. Furthermore, such a device may be embodied or a method may be practiced using other structures, functions, or structures and functions in addition to or instead of one or more of the aspects described herein.

[0027] A radio frequency (RF) communication system according to the present disclosure may be configured to communicate between an RF transmitter and an RF receiver through a plastic waveguide link exhibiting low-loss and wideband channel characteristics. Such a system can improve transmission speeds by simultaneously transmitting and receiving two or more RF signals in dual or multi-band modes through a plastic waveguide at their respective bandwidths. Furthermore, such a system can implement single-sideband transmission by adjusting the cutoff frequency band of each RF signal, thereby enabling twice the data rate compared to double-sideband transmission, further improving transmission speeds.

[0028] FIG. 1 is an exemplary diagram illustrating single-sideband transmission.

[0029] The present disclosure can apply single-sideband transmission as illustrated in FIG. 1 to achieve twice the data rate compared to double-sideband transmission. In one embodiment, the present disclosure can adjust the slope of the upper cutoff frequency band of the signal, and provide a transmit signal centered on the lower sideband signal to the receiver by making the link frequency characteristic sharply rolled off at the upper cutoff frequency (i.e., high roll-off). In another embodiment, the present disclosure can adjust the slope of the lower cutoff frequency band, and provide a transmit signal centered on the upper sideband signal to the receiver by making the link frequency characteristic sharply rolled off at the lower cutoff frequency (i.e., high roll-off).

[0030] As described below, the present disclosure can provide a waveguide link channel that can transmit a larger amount of data while maintaining the power spectrum for each signal by applying the above-mentioned single sideband transmission technique to each of the low band (LB) signal and high band (HB) signal that make up the dual band.

[0031] FIG. 2 is an exemplary diagram illustrating a dual-band plastic waveguide transmission system according to one embodiment of the present disclosure.

[0032] As shown in FIG. 2, such a system may include an RF transmitter 110, an RF receiver 120, a transmitting interconnection device including microstrip-to-waveguide transitions MWTs 140 and 141, a receiving interconnection device including MWTs 142 and 143, duplexers 150 and 151, and a bidirectional plastic waveguide (hereinafter referred to as "E-TUBE") device 130.

[0033] The RF transmitter 110 may be configured to transmit a first signal (Data In[0]) and a second signal (Data In[1]) that have been upconverted at a first carrier frequency (f1) and a second carrier frequency (f2) higher than the first carrier frequency, respectively. To this end, the RF transmitter 110 may include mixers 111 and 112 and power amplifiers (PAs) 113 and 114 for upconverting the first and second signals to the first and second carrier frequencies, respectively. In addition, although not shown in a separate drawing, the RF transmitter 110 may include a phase-locked loop (PLL) for providing a clock signal to the RF transmitter 110, a multiplier for converting the clock signal to a carrier frequency, and the like.

[0034] The RF receiver 120 may be configured to downconvert and receive a first signal and a second signal received at a first carrier frequency and a second carrier frequency, respectively. The RF receiver 120 may be configured to include components corresponding to receiving signals from the RF transmitter 110. For example, the RF receiver 120 may include low noise amplifiers (LNAs) 121 and 122 and downconverting mixers 123 and 124, and may also include a phase synchronizer, a PLL, a multiplier, etc., although not shown in separate drawings.

[0035] The E-TUBE device 130 may be configured to provide a communication channel between the RF transmitter 110 and the RF receiver 120. The E-TUBE device 130 may include a plastic (or dielectric) waveguide for transmitting and receiving signals and a surrounding metal cladding. The metal cladding may confine radio waves and prevent electromagnetic leakage. In one embodiment, the E-TUBE device 130 may include a plastic waveguide with a rectangular cross-section, but the shape of the waveguide is not limited thereto and may be configured to have a different shape, such as a circular cross-section.

[0036] The transmitting interconnection device may be configured to couple between the RF transmitter 110 and the E-TUBE device 130 and may include transmitting MWTs 140 and 141. The receiving interconnection device may be configured to couple between the E-TUBE device 130 and the RF receiver 120 and may include receiving MWTs 142 and 143. Depending on the embodiment, such interconnection devices may be embodied as microstrips, strips, coplanar waveguides, etc.

[0037] The first MWT 142 may be configured to transmit a first signal from the E-TUBE device 130 to the RF receiver 120, and the second MWT 143 may be configured to transmit a second signal from the E-TUBE device 130 to the RF receiver 120. The duplexer 151 may be coupled to the first MWT 142 and the second MWT 143, respectively, and configured to transmit the first signal and the second signal from the E-TUBE device 130. The duplexer 151 may also be configured to combine or split the first signal and the second signal and to prevent crosstalk between the first signal and the second signal. Correspondingly, the duplexer 150 and the MWTs 140 and 141 may be provided between the E-TUBE device 130 and the RF transmitter 110.

[0038] The first signal is a low band (LB) signal 160, and its frequency bandwidth can be adjusted so that it can be received as an upper sideband signal 162 having a predetermined bandwidth based on a first carrier frequency. The second signal is a high band (HB) signal 170, and its frequency bandwidth can be adjusted so that it can be received as a lower sideband signal 172 having a predetermined bandwidth based on a second carrier frequency. To this end, as described below, the frequency bandwidth of the first signal can be adjusted by the E-TUBE device 130 and the first MWT 140, and the frequency bandwidth of the second signal can be adjusted by the E-TUBE device 130 and the second MWT 141. Thus, the first and second signals can be bandwidth-adjusted and received by the RF receiver 120 via the E-TUBE device 130 as single-sideband transmissions, and the RF receiver 120 can receive the first and second signals 162 and 172 with their bandwidths adjusted accordingly. In other words, this system can provide a waveguide link channel that reflects a duplex single-sideband transmission scheme.

[0039] For example, the first carrier frequency (f1) may be 115 GHz and the second carrier frequency (f2) may be 170 GHz, and the first and second signals may be adjusted to be transmitted in a bandwidth of 30 GHz or less based on the corresponding carrier frequencies and received through the E-TUBE device 130. In this case, the first and second signals in the bandwidth of 115 GHz to 170 GHz may be transmitted together as an upper sideband low band (LB) signal and a lower sideband high band (HB) signal through the plastic waveguide of the E-TUBE device 130, thereby realizing dual-band wideband ultra-high speed transmission.

[0040] FIG. 3 is an exemplary plot showing the lower cutoff frequency and upper cutoff frequency of a plastic waveguide channel response.

[0041] The frequency bandwidths of the first signal (i.e., the low-band signal) and the second signal (i.e., the high-band signal) can be adjusted by adjusting the lower cutoff frequency and the upper cutoff frequency, respectively. As shown in FIG. 2, for the first signal (i.e., the low-band signal) 160, the frequency bandwidth of the first signal can be adjusted by adjusting the lower cutoff frequency using the E-TUBE device 130, and can be adjusted by adjusting the upper cutoff frequency using the first MWT 142. In the same manner, for the second signal (i.e., the high-band signal) 170, the frequency bandwidth of the second signal can be adjusted by adjusting the upper cutoff frequency using the E-TUBE device 130, and can also be adjusted by adjusting the lower cutoff frequency using the second MWT 143.

[0042] FIG. 4 is an exemplary diagram illustrating the configuration of a plastic waveguide device according to one embodiment of the present disclosure.

[0043] 4, the E-TUBE device 130 may include a plastic waveguide (i.e., dielectric tube) 310 having a rectangular cross section and a metal cladding 320 surrounding the dielectric tube 310. In such a case, the lower cutoff frequency of the first signal and the upper cutoff frequency of the second signal may be adjusted based on the horizontal length (b) and vertical length (a) of the cross section of the dielectric tube 310.

[0044] Specifically, for the dielectric tube illustrated in FIG. 4, the cutoff frequency (fnm) can be determined by the following formula:

[0045]

number

[0046] where c represents the wave velocity of the dielectric tube and can be determined based on the permittivity (ε1) and permeability (μ1) of the dielectric tube, a represents the longitudinal length of the dielectric tube, b represents the transverse length of the dielectric tube, and n and m are integers representing the mode coefficients of the wave.

[0047] FIG. 5 is an exemplary diagram illustrating a cross-sectional view of a package substrate including an MWT according to one embodiment of the present disclosure.

[0048] The transmission system according to the present disclosure may be configured to connect a transmitter-side board and a receiver-side board through an E-TUBE device 130, and each board may include an IC package. The IC package may include a package substrate 400 on which an RF chip (die) 410 and MWTs 140, 141, 142, and 143 are formed. The IC package may be connected to a printed circuit board (PCB) (not shown) through solder balls 420.

[0049] In one embodiment, the RF chip 410 may be disposed at the bottom of the package substrate 400 and attached to the package substrate 400 using bumps 421. Also, a via 422 serving as a transmission path for an RF signal may be formed between the RF chip 410 and the package substrate 400.

[0050] The MWTs 140, 141, 142, and 143 may include a feeding line 430, a probe element 440, and a slotted ground plane 450. The feeding line 430 may supply an RF signal through a via 422 formed between the RF chip 410 and the package substrate 400. The probe element 440 may receive an RF signal from the feeding line 430 and radiate the RF signal to the slotted ground plane 450. The slotted ground plane 450 may allow the signal radiated from the probe element 440 to pass through and be transmitted to the E-TUBE device 130. The MWTs 140, 141, 142, and 143 may be connected to the E-TUBE device 130 through duplexers 150 and 151.

[0051] As described above, a first signal (i.e., a low-band signal) may be transmitted to the first MWT 142, and a second signal (i.e., a high-band signal) may be transmitted to the second MWT 143. Here, the probe element 440 and slotted ground plane 450 of each MWT may be used to adjust the frequency bandwidth of the corresponding signal. Specifically, the upper cutoff frequency of the first signal may be adjusted based on the length of the probe element 440 of the first MWT 142 and the slot size of the slotted ground plane 450 of the first MWT 142. Also, the lower cutoff frequency of the second signal may be adjusted based on the length of the probe element 440 of the second MWT 143 and the slot size of the slotted ground plane 450 of the second MWT 143.

[0052] FIG. 6a is an exemplary diagram showing the slotted ground plane of plane A-A' of FIG.

[0053] 6a, slots for low-band signals (LB) and high-band signals (HB) may be formed on a slotted ground plane 450. Here, increasing the horizontal lengths 510, 511 of the slots may decrease the cutoff of the corresponding signals, and decreasing the horizontal lengths 510, 511 may increase the cutoff of the corresponding signals.

[0054] FIG. 6b is an exemplary diagram showing the probe element located in the BB' plane of FIG.

[0055] 6b, a probe element 440 for a low-band signal (LB) and a probe element 440 for a high-band signal (HB) may be formed on the B-B' plane of the package substrate 400. Here, as the vertical lengths 520 and 521 of the probe elements 440 increase, the cutoff of the corresponding signal may decrease, and as the vertical lengths 520 and 521 decrease, the cutoff of the corresponding signal may increase.

[0056] FIG. 7 is an exemplary diagram illustrating a multi-band plastic waveguide transmission system according to one embodiment of the present disclosure.

[0057] The plastic waveguide transmission system according to the present disclosure can be realized as a dual-band transmission system that transmits two RF signals, as well as a multi-band transmission system that can transmit multiple RF signals. The multi-band transmission system can be realized by adding a low-band signal that is lower than the low-band signal of the dual-band transmission system and a high-band signal that is higher than the high-band signal.

[0058] As illustrated in FIG. 7, when implemented in a multi-band transmission system capable of transmitting four RF signals, the RF receiver 620 may be configured to receive from the RF transmitter 610 a first signal transmitted at a first carrier frequency (f1), a second signal transmitted at a second carrier frequency (f2) higher than the first carrier frequency, a third signal transmitted at a third carrier frequency (f0) lower than the first carrier frequency, and a fourth signal transmitted at a fourth carrier frequency (f3) higher than the second carrier frequency.

[0059] In such a multi-band transmission system, the interconnection device may include a first MWT 640 configured to transmit a first signal from the E-TUBE device 130 to the RF receiver 620, a second MWT 641 configured to transmit a second signal from the E-TUBE device 130 to the RF receiver 620, a third MWT 642 configured to transmit a third signal from the E-TUBE device 130 to the RF receiver 620; and a fourth MWT 643 configured to transmit a fourth signal from the E-TUBE device 130 to the RF receiver 620.

[0060] The frequency bandwidth of a first signal may be adjusted by the E-TUBE device 130 and the first MWT 640 so that the first signal is received as an upper sideband signal. The frequency bandwidth of a second signal may be adjusted by the E-TUBE device 130 and the second MWT 641 so that the second signal is received as a lower sideband signal. The frequency bandwidth of a third signal may be adjusted by the E-TUBE device 130 and the third MWT 642 so that the third signal is received as an upper sideband signal. The frequency bandwidth of a fourth signal may be adjusted by the E-TUBE device 130 and the fourth MWT 643 so that the fourth signal is received as a lower sideband signal.

[0061] Such a multi-band transmission system may include a quadplexer 650 for transmitting the first signal, the second signal, the third signal, and the fourth signal from the E-TUBE device 130 .

[0062] Additionally, the RF transmitter 610 may be configured to include corresponding components for transmitting signals to the RF receiver 620, and a corresponding quadplexer and MWT may be provided between the E-TUBE device 130 and the RF transmitter 610.

[0063] In such a case, the frequency bandwidth of the first signal and the frequency bandwidth of the third signal can be adjusted by adjusting the lower cutoff frequency by the E-TUBE device 130, and the frequency bandwidth of the second signal and the frequency bandwidth of the fourth signal can be adjusted by adjusting the upper cutoff frequency by the E-TUBE device 130.

[0064] In addition, the frequency bandwidth of the first signal can be adjusted by adjusting the upper cutoff frequency using the first MWT 640, the frequency bandwidth of the second signal can be adjusted by adjusting the lower cutoff frequency using the second MWT 641, the frequency bandwidth of the third signal can be adjusted by adjusting the upper cutoff frequency using the third MWT 642, and the frequency bandwidth of the fourth signal can be adjusted by adjusting the lower cutoff frequency using the fourth MWT 643.

[0065] The adjustment of the lower cutoff frequency and the upper cutoff frequency by the E-TUBE device 130 and the MWTs 640, 641, 642, and 643 can be performed in the same manner as described above with reference to FIGS.

[0066] The description of the embodiments presented is provided to enable any person skilled in the art to make or practice the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments presented herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. 1. An RF communication system comprising: an RF receiver configured to receive a first signal and a second signal transmitted from an RF transmitter at a first carrier frequency and a second carrier frequency higher than the first carrier frequency, respectively; a plastic waveguide device configured to provide a communication channel between the RF transmitter and the RF receiver; an interconnection device including a first microstrip-to-waveguide transition (MWT) configured to transmit the first signal from the plastic waveguide device to the RF receiver and a second MWT configured to transmit the second signal from the plastic waveguide device to the RF receiver; a frequency bandwidth of the first signal is adjusted by the plastic waveguide device and the first MWT so that the first signal is received as an upper sideband signal, and a frequency bandwidth of the second signal is adjusted by the plastic waveguide device and the second MWT so that the second signal is received as a lower sideband signal.

2. The RF communication system of claim 1 , further comprising a duplexer coupled to the first MWT and the second MWT, respectively, for transmitting the first signal and the second signal from the plastic waveguide device.

3. 2. The RF communication system of claim 1, wherein the frequency bandwidth of the first signal is adjusted by adjusting a lower cut-off frequency of the plastic waveguide device, and the frequency bandwidth of the second signal is adjusted by adjusting an upper cut-off frequency of the plastic waveguide device.

4. the plastic waveguide device includes a dielectric tube having a rectangular cross section; 4. The RF communication system of claim 3, wherein the lower cutoff frequency of the first signal and the upper cutoff frequency of the second signal are adjusted based on the horizontal length and vertical length of the cross section of the dielectric tube.

5. 2. The RF communication system of claim 1, wherein the frequency bandwidth of the first signal is adjusted by adjusting an upper cutoff frequency with the first MWT, and the frequency bandwidth of the second signal is adjusted by adjusting a lower cutoff frequency with the second MWT.

6. Each of the first MWT and the second MWT is a probe element that receives a signal from the feeding line; and 6. The RF communication system of claim 5, including a slotted ground plane through which signals radiated from said probe element are transmitted to said plastic waveguide device.

7. an upper cutoff frequency of the first signal is adjusted based on a length of a probe element of the first MWT and a slot size of a slotted ground plane of the first MWT; 7. The RF communication system of claim 6, wherein a lower cutoff frequency of the second signal is adjusted based on a length of a probe element of the second MWT and a slot size of a slotted ground plane of the second MWT.

8. The RF receiver includes: additionally configured to receive a third signal and a fourth signal transmitted from the RF transmitter at a third carrier frequency lower than the first carrier frequency and a fourth carrier frequency higher than the second carrier frequency, respectively; The interconnection device comprises: a third MWT configured to transmit the third signal from the plastic waveguide device to the RF receiver; and further comprising a fourth MWT configured to transmit the fourth signal from the plastic waveguide device to the RF receiver; 2. The RF communication system of claim 1, wherein the frequency bandwidth of the third signal is adjusted by the plastic waveguide device and the third MWT so that the third signal is received as an upper sideband signal, and the frequency bandwidth of the fourth signal is adjusted by the plastic waveguide device and the fourth MWT so that the fourth signal is received as a lower sideband signal.

9. 9. The RF communication system of claim 8, further comprising a quadplexer for transmitting the first signal, the second signal, the third signal, and the fourth signal from the plastic waveguide device.

10. 9. The RF communication system of claim 8, wherein the frequency bandwidth of the first signal and the frequency bandwidth of the third signal are adjusted by adjusting a lower cutoff frequency by the plastic waveguide device, and the frequency bandwidth of the second signal and the frequency bandwidth of the fourth signal are adjusted by adjusting an upper cutoff frequency by the plastic waveguide device.

11. 9. The RF communication system of claim 8, wherein the frequency bandwidth of the first signal is adjusted by adjusting an upper cutoff frequency by the first MWT, the frequency bandwidth of the second signal is adjusted by adjusting a lower cutoff frequency by the second MWT, the frequency bandwidth of the third signal is adjusted by adjusting an upper cutoff frequency by the third MWT, and the frequency bandwidth of the fourth signal is adjusted by adjusting a lower cutoff frequency by the fourth MWT.

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