Tunable, broadband directional coupler circuits employing an additional, selectable coupling circuit(s) for controlling frequency response

Abstract

A tunable broadband directional coupler circuit and related methods are disclosed, employing one or more additional switchable coupling circuits for controlling the frequency response. In an exemplary embodiment, the directional coupler includes one or more additional coupling circuits, each including an additional coupling line positioned adjacent to the main coupling line and selectively activated to alter the frequency response of the directional coupler. When an additional coupling circuit is activated, its additional coupling line, via mutual inductance, extends the length of the main coupling line, thereby altering the coupling frequency response of the directional coupler. The additional coupling circuit includes one or more switches to allow selective coupling of its additional coupling line to the coupling and / or isolation ports of the directional coupler to selectively change and control the frequency response of the main coupling line.

Description

Technical Field

[0001] The field of this case concerns directional couplers, and more specifically, the use of directional couplers to couple power from a radio frequency (RF) signal into a representative signal to be supplied to another circuit for a desired application. Prior Technology

[0002] Generally, radio frequency (RF) transmitting circuit chains typically include an RF power amplifier (PA) to amplify a transmitted RF signal into an output RF signal within a given frequency band. It may be desirable to detect the output power in the output RF signal. For example, the detected output power can be used to adjust the gain of the PA to control the output power in the output RF signal within a given output power level or range. In this regard, a directional coupler can be provided and coupled to the transmission line of the RF transmitting circuit chain to detect the output power of the output RF signal. A directional coupler is a passive electrical device that couples the power of a signal transmitted in the transmission line to a port, thereby enabling the representation of the coupled signal to be supplied to another circuit for a desired application. In this example, the directional coupler is coupled to the transmission line at the output side of the RF PA to sample the output RF signal from the RF PA and pass the sampled output RF signal to a power detector. The power detector can be configured to generate a control signal based on the power detected in the output RF signal to adjust the gain of the RF PA.

[0003] Directional couplers, by their design, have an operating frequency response (i.e., frequency range). The operating frequency response of a directional coupler is defined as the range of signal frequencies that the directional coupler can couple on its coupled output port at a given minimum specified coupling power. For example, a directional coupler may be able to couple RF signals at a minimum power level of 20 dB within a limited frequency range between 100-1600 MHz. It may be desirable to provide directional couplers with a large bandwidth for desired applications. For example, in 5G New Radio (5G-NR) mobile network applications, there may be multiple feedback receiver paths spanning a wide frequency range that require power measurement. Summary of the Invention

[0004] The various embodiments disclosed herein include tunable broadband directional coupler circuits employing one or more additional switchable coupling circuits for controlling the frequency response. Related methods are also disclosed. The directional coupler circuit includes a directional coupler having a main transmission line coupled between an input port and an output port. The main transmission line is configured to transmit a received radio frequency (RF) signal received at the input port to the output port. The directional coupler also includes a main coupling line adjacent to the main transmission line and coupled between an isolation port and a coupling port. The main coupling line couples a portion of the electromagnetic (EM) power of the RF signal on the main coupling line to the additional coupling lines(s). In an exemplary embodiment, to allow selective tuning of the frequency response of the directional coupler, the directional coupler circuit includes one or more additional coupling circuits. Each additional coupling circuit includes a corresponding coupling line positioned adjacent to the main coupling line. When an additional coupling circuit is activated, its additional coupling line, via mutual inductance between the main coupling line and the additional coupling line, has the effect of extending the length of the main coupling line. This alters the coupled frequency response at the coupling port of the directional coupler. In one exemplary configuration, the additional coupling circuitry includes a port switch coupled between its additional coupling line and the coupling port. In another exemplary configuration, the additional coupling circuitry includes an isolation port switch coupled between its additional coupling line and the isolation port. These port switches and / or isolation port switches can be selectively activated in various combinations to activate the corresponding additional coupling circuitry in the directional coupler to alter the frequency response of the coupling port. Thus, the frequency response of the directional coupler can be tuned and varied across different frequency ranges to achieve a wider overall frequency response capability.

[0005] In one exemplary embodiment, a directional coupler circuit is provided. The directional coupler circuit includes a main transmission line coupled between an input port and an output port. The directional coupler circuit also includes a main coupling circuit comprising a main coupling line adjacent to the main transmission line. The directional coupler circuit further includes an additional coupling circuit. The additional coupling circuit includes an additional coupling line comprising a first end and a second end, the additional coupling line being adjacent to the main coupling line.

[0006] In another exemplary embodiment, a method for selectively tuning the frequency response of a directional coupler is provided. The method includes receiving an input RF signal at an input port coupled to a main transmission line. The method also includes transmitting the received input RF signal to an output port on the main transmission line. The method further includes coupling a portion of the power of the input RF signal as a coupled RF signal from the main transmission line to a main coupling line adjacent to the main transmission line to provide a main coupled RF signal having a main frequency response. The method also includes activating an additional coupling line adjacent to the main coupling line to couple a portion of the coupled RF signal to the additional coupling line to provide an additional coupled RF signal having a second frequency response different from the main frequency response.

[0007] In another exemplary embodiment, an RF transmitting circuit is provided. The RF transmitting circuit includes a power amplifier (PA) circuit. The PA circuit includes: a PA input configured to receive an input RF signal; and a PA output. The PA circuit is configured to amplify the input RF signal into an amplified RF signal at the PA output. The RF transmitting circuit also includes a matching network circuit. The matching network circuit includes: a matching network input coupled to the PA output, and a matching network output. The RF transmitting circuit also includes a directional coupler circuit. The directional coupler circuit includes a coupler input port coupled to the matching network output, a coupler output port, and a main transmission line coupled to the coupler input port and the coupler output port. The directional coupler circuit also includes a main coupling circuit including a main coupling line adjacent to the main transmission line. The directional coupler circuit also includes an additional coupling circuit. The additional coupling circuit includes an additional coupling line including a first end and a second end, wherein the additional coupling line is adjacent to the main coupling line. The additional coupling circuit also includes an additional coupling port switch coupled to the first end of the additional coupling line and the coupled output. The additional coupling circuit also includes a second end coupled to the additional coupling line and an additional isolation port switch for the isolated output. Simple Explanation of the Diagram

[0008] Figure 1 is a schematic diagram of a radio frequency (RF) transmitter circuit chain that uses a directional coupler to couple the power from the output RF signal;

[0009] Figure 2 is a schematic diagram of an exemplary tunable broadband directional coupler circuit employing an additional coupling circuit for controlling the frequency response of the directional coupler;

[0010] Figure 3 is a schematic diagram of another exemplary tunable broadband directional coupler circuit employing an additional switchable coupling circuit for controlling the frequency response of the directional coupler;

[0011] Figure 4 is a table illustrating exemplary operating modes for controlling the activation of the main coupling circuit and the auxiliary coupling circuit in the directional coupler of Figure 3 to allow selective tuning of the frequency response of the directional coupler;

[0012] Figure 5 is a graph illustrating different exemplary frequency responses of the directional coupler in Figure 3 based on different operating modes of the directional coupler;

[0013] Figure 6 is an exemplary circuit layout diagram illustrating the exemplary circuit element layout of the directional coupler in Figure 3;

[0014] Figure 7 is a schematic diagram of another exemplary tunable broadband directional coupler circuit employing multiple additional switchable coupling circuits for controlling the frequency response of the directional coupler;

[0015] Figure 8 is a table illustrating exemplary operating modes for controlling the activation of the main coupling circuit and multiple auxiliary coupling circuits in the directional coupler of Figure 7 to selectively tune the frequency response of the directional coupler;

[0016] Figure 9 is an exemplary circuit layout diagram illustrating the exemplary circuit element layout of the directional coupler in Figure 7;

[0017] Figure 10 is a schematic diagram of another exemplary tunable broadband directional coupler circuit that employs any number of up to 'N' additional switchable coupling circuits to allow selective tuning of the frequency response of the directional coupler; and

[0018] Figure 11 is a block diagram of an exemplary wireless communication device, which may include a tunable broadband directional coupler circuit employing additional switchable coupling circuitry for controlling the frequency response of directional couplers (including, but not limited to, the tunable broadband directional couplers in Figures 2-3, 5-6 and 8-9). Implementation

[0019] Now, with reference to the accompanying drawings, several exemplary forms of this case are described. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any form described herein as "exemplary" is not necessarily to be construed as superior to or better than other forms.

[0020] The various embodiments disclosed herein include tunable broadband directional coupler circuits employing one or more additional switchable coupling circuits for controlling the frequency response. Related methods are also disclosed. The directional coupler circuit includes a directional coupler having a main transmission line coupled between an input port and an output port. The main transmission line is configured to transmit received radio frequency (RF) signals received at the input port to the output port. The directional coupler also includes a main coupling line adjacent to the main transmission line and coupled between an isolation port and a coupling port. The main coupling line couples a portion of the electromagnetic (EM) power of the RF signal on the main coupling line to the additional coupling lines(s). In an exemplary embodiment, to allow selective tuning of the frequency response of the directional coupler, the directional coupler circuit includes one or more additional coupling circuits. Each additional coupling circuit includes a corresponding coupling line positioned adjacent to the main coupling line. When an additional coupling circuit is activated, its additional coupling line, via mutual inductance between the main coupling line and the additional coupling line, has the effect of extending the length of the main coupling line. This alters the coupled frequency response at the coupling port of the directional coupler. In one exemplary configuration, the additional coupling circuitry includes a port switch coupled between its additional coupling line and the coupling port. In another exemplary configuration, the additional coupling circuitry includes an isolation port switch coupled between its additional coupling line and the isolation port. These port switches and / or isolation port switches can be selectively activated in various combinations to activate the corresponding additional coupling circuitry in the directional coupler to alter the frequency response of the coupling port. Thus, the frequency response of the directional coupler can be tuned and altered to various different frequency ranges to achieve a wider overall frequency response capability.

[0021] In this regard, Figure 1 illustrates an exemplary RF transmitting circuit 100 employing a directional coupler 102 configured to couple power from an output RF signal amplified by a power amplifier (PA) circuit 104. The PA circuit 104 is an amplifier circuit configured to amplify a received input RF signal 106 into an output RF signal 108. The output RF signal 108 may be coupled to a matching network 110 to provide impedance matching between the output 112 of the PA circuit 104 and a main transmission line 114 carrying the output RF signal 108 to another destination circuit. For example, the PA circuit 104 and the matching network 110 may be part of an RF front-end circuit 115 provided in a communication device, such as a mobile cellular telephone. The RF front-end circuit 115 may be coupled to an antenna (not shown) that receives the input RF signal 106 and couples it to the PA circuit 104 for amplification.

[0022] To sample a portion of the output RF signal 108 to be supplied to another circuit for analysis (such as for power measurement and amplifier feedback), the RF transmitting circuit 100 in FIG1 also includes a directional coupler 102. The directional coupler 102 is a passive electrical device that couples the output RF signal 108 to the output port 116 in the main transmission line 114. The directional coupler 102 also includes a main coupling line 118, which is positioned adjacent to the main transmission line 114 to electromagnetically couple a portion of the power of the output RF signal 108 as a coupled RF signal 122 to the coupling port 120. The directional coupler 102 also includes an isolation port 124. The directional coupler 102 can be configured in a forward mode to supply the coupled RF signal 122 to the coupling port 120, or in a reverse mode to supply the coupled RF signal 122 to the isolation port 124.

[0023] The directional coupler 102 in Figure 1 has an operating frequency response (i.e., frequency range) according to its design. In this example, the length of the main coupling line 118 is one-quarter of the wavelength at the center frequency of the frequency response of the directional coupler 102. The operating frequency response of the directional coupler is defined as the range of signal frequencies centered on its center frequency that the directional coupler 102 can couple to the output RF signal 108 at a given minimum specified coupling power. For example, it might be desirable for the directional coupler 102 to couple the output RF signal 108 at a minimum power level of 20 dB within a limited frequency range between 100 and 2600 MHz for applications such as fifth-generation (5G) radio (NR) (5G-NR) mobile networks. However, the frequency response of the main coupling line 118 may not provide this desired frequency response.

[0024] In this regard, Figure 2 is a schematic diagram of an exemplary tunable broadband directional coupler 200 capable of providing a coupled RF output signal with an extended frequency response. In this example, the directional coupler 200 is provided as part of a directional coupler circuit 202. The directional coupler 200 includes a main transmission line 204 coupled between an input port 206 and an output port 208. The input port 206 is configured to receive an input RF signal 210. The main transmission line 204 couples the input RF signal 210 to the output port 208. To generate a main coupled RF signal 212 from the input RF signal 210, the directional coupler 200 also includes a main coupling circuit 214. The main coupling circuit 214 includes a main coupling line 216 positioned adjacent to the main transmission line 204 as a transmission line. The main coupling line 216 is positioned sufficiently close to the main transmission line 204 such that the EM field generated by the input RF signal 210 passing through the main transmission line 204 induces a current in the main coupling line 216. The current induced on the main coupling line 216 is a representation of the input RF signal 210, but a portion of the power of the input RF signal 210 is used as the main coupled RF signal 212. Depending on whether the directional coupler 200 is controlled to operate in forward or reverse modes, the main coupled RF signal 212 can be provided on the main coupling line 216 to either the coupling port 218 or the isolation port 220. In this example in Figure 2, the directional coupler 200 is shown operating in forward mode.

[0025] The main coupling circuit 214 has a dominant frequency response. The center frequency of the dominant frequency response of the main coupling circuit 214 depends on the length of the main coupling line 216. The dominant frequency response of the main coupling line 216 also controls the frequency bandwidth of the input RF signal 210 that can be coupled in the main coupled RF signal 212 at a given power level. The dominant frequency response of the main coupling circuit 214 is the coupling frequency response of the directional coupler 200. Based on the frequency response of the main coupling circuit 214 in the directional coupler 200, the dominant frequency response of the directional coupler 200 may not cover the desired frequency range of the desired input RF signal 210. For example, the main coupling circuit 214 of the directional coupler 200 in Figure 2 may be able to couple the input RF signal 210 at a minimum power level of 20 dB within a limited frequency range between 100-1600 MHz. However, it may be desirable for the directional coupler 200 to have a frequency response with a larger bandwidth for the desired application. For example, in 5G-NR mobile network applications, there may be multiple feedback receiving paths across a wide frequency range (such as between 100-2300 MHz) that require power measurement.

[0026] In this regard, to modify the frequency bandwidth and frequency response of the directional coupler 200 in Figure 2, the directional coupler 200 includes an additional coupling circuit 222 in this example. The additional coupling circuit 222 includes an additional coupling line 224, which includes a first end 226 coupled to coupling port 218 and a second end 228 coupled to isolation port 220. The additional coupling line 224 is positioned adjacent to the main coupling line 216. The additional coupling line 224 is positioned sufficiently close to the main coupling line 216 such that the EM field generated as a result of coupling the main coupled RF signal 212 on the main coupling line 216 induces a current on the additional coupling line 224. The current induced on the additional coupling line 224 is a representation of the main coupled RF signal 212, but with a portion of the power of the main coupled RF signal 212 as the additional coupled RF signal 230. The mutual inductance between the additional coupling line 224 and the main coupling line 216 via the main coupling line 216 has the effect of extending the length of the main coupling line 216. This changes the coupling frequency response on coupling port 218 of directional coupler 200 to a second frequency response. As a result, additional coupling circuit 222 allows the frequency response of directional coupler 200 to be changed to respond to an input RF signal 210 in a different second frequency range (which would normally only respond if the main coupling line 216 is present and active to achieve a frequency response capability different from the main frequency response).

[0027] It may also be desirable to provide the ability to selectively tune the frequency response of the directional coupler 200 in Figure 2. For example, if the additional coupling circuit 222 is not coupled to the coupling port 218 or the isolation port 220 of the directional coupler 200, the frequency response of the directional coupler 200 at the coupling port 218 will be based on the coupling from the power of the input RF signal 210 to the main coupling line 216 itself. However, if the additional coupling circuit 222 is coupled to the coupling port 218 or the isolation port 220 of the directional coupler 200, the frequency response of the directional coupler 200 at the coupling port 218 will be based on the coupling from the power of the input RF signal 210 to the main coupling line 216 and its coupling via the additional coupling line 224 of the mutual inductance of the additional coupling circuit 222.

[0028] In this regard, Figure 3 is a schematic diagram of another directional coupler 300 in the directional coupler circuit 302, where the directional coupler 300 is similar to the directional coupler 200 in Figure 2. The directional coupler circuit 302 and its directional coupler 300 in Figure 3 include an alternative additional coupling circuit 322 similar to the additional coupling circuit 222 in Figure 2. However, as discussed in more detail below, the additional coupling circuit 322 in Figure 3 includes an additional switchable coupling port switch S5 and an isolation port switch S6, which can be activated (i.e., closed) or deactivated (i.e., open) to control whether the additional coupling circuit 322 (and more specifically, its additional coupling line 224) is coupled and electrically active in the directional coupler circuit 302. This allows the frequency response of the directional coupler 300 to be tuned between including the additional coupling circuit 322 in the directional coupler circuit 302 and without the additional coupling circuit 322. In this way, the directional coupler 300 can be configured to provide a wider frequency response. As discussed in more detail below, the directional coupler circuit 302 also includes first and second main coupling port switches S4, S3 and first and second main isolation port switches S1, S2 to control whether the directional coupler 300 is in a forward or reverse operating mode between coupling port 218 and isolation port 220.

[0029] In this regard, as illustrated in Figure 3, the additional coupling circuit 322 includes an additional coupling line 224 similar to the additional coupling circuit 222 in Figure 2. Common elements between the directional coupler circuit 202 in Figure 2 and the directional coupler circuit 302 in Figure 3 are shown with common component numbers and are therefore not described further. The additional coupling circuit 322 includes a first terminal 226 coupled to the additional coupling line 224 and an additional coupling port switch S5 coupling the output CPL_OUT. The additional coupling circuit 322 also includes a second terminal 228 coupled to the additional coupling line 224 and an additional isolation port switch S6 isolating the output GND (which is the ground node in this example). The additional coupling port switch S5 is configured to be activated (i.e., closed) to couple the first end 226 of the additional coupling line 224 to the coupling output CPL_OUT, so that the directional coupler 300 and the main coupled RF signal 212 have a second frequency response different from the main frequency response (when the additional coupling circuit 322 is not actively included in the directional coupler circuit 302 and coupled to the coupling output CPL_OUT). When the additional coupling port switch S5 is activated, the additional coupling line 224 is EM-coupled to the main coupling line 216, so that the main coupled RF signal 212 has a second frequency response different from the main frequency response. The EM coupling from the additional coupling line 224 to the main coupling line 216 effectively lengthens the main coupling line 216, and thereby lengthens its wavelength response.

[0030] This is further illustrated in Table 400 of Figure 4, which explains exemplary operating modes for controlling the activation of the main coupling circuit 214 and the additional coupling circuit 322 in the directional coupler 300 of Figure 3 to allow selective tuning of the frequency response of the directional coupler. As shown in Table 400, when the additional coupling port switch S5 is activated (closed or "on") and the additional isolation port switch S6 is deactivated (open or "off"), the directional coupler 300 has a second frequency response (#2) in mode 2. This is illustrated in frequency response curve 502 in graph 500 of Figure 5, which plots the power level of the main longitudinally coupled RF signal 212 on the Y-axis as a frequency (f) dependent on the X-axis. As shown in Figure 5, the frequency response of the main longitudinally coupled RF signal 212 above power level '4' in mode 2 is 2300 to 2700 MHz. This differs from the first frequency response (#1) in Mode 1 shown in Table 400 of Figure 4 (when neither the additional coupling port switch S5 nor the additional isolation port switch S6 is activated to provide the additional coupling circuit 322 in the directional coupler circuit 302). The first frequency response of the directional coupler 300 for Mode 1 is illustrated in frequency response curve 504 in graph 500 of Figure 5, which explains that the frequency response of the primary coupled RF signal 212 above power level '4' in Mode 1 is between 663 and 917 MHz.

[0031] Similarly, the additional isolation port switch S6 is configured to be activated (i.e., closed) to couple the second end 228 of the additional coupling line 224 to the isolation output GND, such that the directional coupler 300 and the main coupled RF signal 212 have a third frequency response different from the main frequency response (when the additional coupling circuit 322 is not actively included in the directional coupler circuit 302 and coupled to the isolation output GND). When the additional isolation port switch S6 is activated, the additional coupling line 224 is EM-coupled to the main coupling line 216 to give the main coupled RF signal 212 a third frequency response different from the main frequency response. The EM coupling of the additional coupling line 224 to the main coupling line 216 effectively lengthens the main coupling line 216, thereby lengthening its wavelength response. Coupling the additional coupling line 224 to the isolation output GND changes the frequency response of the directional coupler 300 to a third frequency response different from the second frequency response (when the additional coupling line 224 is coupled to the coupling output CPL_OUT).

[0032] This is further illustrated in Table 400 of Figure 4, which explains exemplary operating modes for controlling the activation of the main coupling circuit 214 and the additional coupling circuit 322 in the directional coupler 300 of Figure 3 to allow selective tuning of the frequency response of the directional coupler 300. As shown in Table 400, when the additional isolation port switch S6 is activated (closed or "on") and the additional coupling port switch S5 is deactivated (open or "off"), the directional coupler 300 has a third frequency response (#3) in mode 3. The third frequency response of the directional coupler 300 for mode 3 is illustrated in frequency response curve 506 in graph 500 of Figure 5. The third frequency response of the main coupled RF signal 212 above power level '4' in mode 3 is between 1500 and 1800 MHz. This differs from the first frequency response (#1) in Mode 1 shown in Table 400 of Figure 4 (when neither the additional coupling port switch S5 nor the additional isolation port switch S6 is activated to provide the additional coupling circuit 322 in the directional coupler circuit 302). As previously mentioned, in this example, the first frequency response of the directional coupler 300 is illustrated in frequency response curve 502 in graph 500 of Figure 5, which illustrates the frequency response of the primary coupled RF signal 212 above power level '4' in Mode 1 between 663 MHz and 917 MHz.

[0033] It may also be desirable to control the forward or reverse operation of the directional coupler 300 with respect to the direction of the main coupled RF signal 212 to the coupling port 218 or the isolation port 220, respectively. In this regard, the main coupling circuit 214 includes additional switches S1-S4, as shown in FIG3, for controlling the forward or reverse operation of the directional coupler 300. Furthermore, as discussed above, the activation and deactivation of the additional coupling port switch S5 and the additional isolation port switch S6 control the frequency response modes 1-3 of the directional coupler 300. The main coupling circuit 214 includes a first main coupling port switch S4 coupled to a first terminal 226 of the main coupling line 216 and coupled to the output CPL_OUT. The main coupling circuit 214 also includes a first main isolation port switch S1 coupled to a second terminal 228 of the main coupling line 216 and coupled to the output GND. The main coupling circuit 214 also includes a second main coupling port switch S3 coupled to a second terminal 228 of the main coupling line 216 and coupled to the output CPL_OUT. The main coupling circuit 214 also includes a second main isolation port switch S2 coupled to a first terminal 226 of the main coupling line 216 and an isolation output GND. The first main coupling port switch S4 and the first main isolation port switch S1 are activated and deactivated together to control the forward operating mode of the directional coupler 300. The second main coupling port switch S3 and the second main isolation port switch S2 are activated and deactivated together to control the reverse operating mode of the directional coupler 300. When the first main coupling port switch S4 and the first main isolation port switch S1 are activated, the second main coupling port switch S3 and the second main isolation port switch S2 should be deactivated, and vice versa.

[0034] In forward mode operation, the first main coupling port switch S4 is configured to be activated to couple the first end 226 of the main coupling line 216 to the coupling output CPL_OUT. Furthermore, in this forward mode operation, the first main isolation port switch S1 is also configured to be activated to couple the second end 228 of the main coupling line 216 to the isolation output GND. In forward mode operation, the main coupled RF signal 212 is directed to the coupling output CPL_OUT in the forward direction. An optional RC filter circuit 304 is coupled between the second end 228 of the main coupling line 216 and the isolation output GND to provide additional frequency isolation between the main coupling line 216 and the isolation output GND. In reverse mode operation, the second main coupling port switch S3 is configured to be activated to couple the second end 228 of the main coupling line 216 to the coupling output CPL_OUT. Furthermore, in this reverse mode operation, the second isolation coupling port switch S2 is also configured to be activated to couple the first end 226 of the main coupling line 216 to the isolation output GND. In reverse mode operation, the master-coupled RF signal 212 is directed to the isolated output GND in the reverse direction.

[0035] Figure 6 is an exemplary circuit layout 600 illustrating an exemplary layout of the directional coupler circuit 302 in Figure 3, further illustrating the exemplary arrangement of the main coupling line 216 and the auxiliary coupling line 224. As illustrated in Figure 6, the main coupling line 216 is arranged as a spiral-shaped metal wire, partially located inside and adjacent to the main transmission line 204. The auxiliary coupling line 224 is arranged as a metal wire partially located inside and adjacent to the main coupling line 216, such that there is mutual inductive coupling between the main coupling line 216 and the auxiliary coupling line 214. A first end 602 of the main coupling line 216 is coupled to a first main isolation port switch S1 and a second isolation coupling port switch S2. A second end 604 of the main coupling line 216 is coupled to a second main coupling port switch S3 and a first main coupling port switch S4. A first end 226 of the auxiliary coupling line 224 is coupled to an auxiliary coupling port switch S5, which is coupled to the coupling output CPL_OUT. The second end 228 of the additional coupling line 224 is coupled to the additional isolation port switch S6, which is coupled to the isolation output GND. As illustrated in FIG6, the main coupling line 216 is arranged as a spiral metal wire, partially located inside and adjacent to the main transmission line 204. The additional coupling line 224 is positioned adjacent to the main coupling line 216.

[0036] In addition to the three frequency responses discussed in modes 1-3 above, it may be desirable to provide additional frequency responses for the directional coupler 300 in the directional coupler circuit 302 of FIG. 3. In this regard, FIG. 7 is a schematic diagram of another exemplary tunable broadband directional coupler 700 in the directional coupler circuit 702, which employs a second additional switchable coupling line 724 in a second additional switchable coupling circuit 722 for controlling the additional frequency response of the directional coupler 700. The directional coupler 700 in FIG. 7 includes the main coupling line 216 and the additional coupling line 224 provided in the directional coupler 300 of FIG. 3. Common elements between the directional coupler 700 and directional coupler circuit 702 in FIG. 7 and the directional coupler 300 and directional coupler circuit 302 in FIG. 3 are shown with common element numbers and are therefore not described further.

[0037] Referring to Figure 7, the second additional coupling circuit 722 includes a second additional coupling line 724 positioned adjacent to the additional coupling line 224. The second additional coupling line 724 is configured to EM-couple to the additional coupling line 224 so that the main coupled RF signal 212 has a different frequency response than previously discussed. The EM coupling of the second additional coupling line 724 to the additional coupling line 224 effectively lengthens the main coupling line 216, and thereby lengthens its wavelength response. The second additional coupling circuit 722 in Figure 7 includes a second additional switchable coupling port switch S7 and an isolation port switch S8, which can be activated (i.e., closed) or deactivated (i.e., open) to control whether the second additional coupling circuit 722 (and more specifically, its second additional coupling line 724) is coupled and electrically active in the directional coupler circuit 702. This allows the frequency response of the directional coupler 700 to be further tunable between the inclusion of the second additional coupling circuit 722 or the absence of the second additional coupling circuit 722 in the directional coupler circuit 702. In this way, the directional coupler 700 can be configured to provide a much wider frequency response.

[0038] The second additional coupling circuit 722 includes a second additional coupling port switch S7 coupled to a first terminal 726 of the second additional coupling line 724 and a coupling output CPL_OUT. The second additional coupling circuit 722 also includes a second additional isolation port switch S8 coupled to a second terminal 728 of the second additional coupling line 724 and an isolation output GND. The second additional coupling port switch S7 is configured to be activated (i.e., closed) to couple the first terminal 726 of the second additional coupling line 724 to the coupling output CPL_OUT, so that the directional coupler 700 and the main coupled RF signal 212 have a different frequency response than those previously discussed (in the case where the second additional coupling circuit 722 is not actively included in the directional coupler circuit 702 and coupled to the coupled output CPL_OUT). When the second additional coupling port switch S7 is activated, the second additional coupling line 724 is EM-coupled to the additional coupling line 224 and / or the main coupling line 216, so that the main coupled RF signal 212 has a different frequency response. The EM coupling of the second additional coupling line 724 to the additional coupling line 224 and / or the main coupling line 216 actually lengthens the main coupling line 216, and thus lengthens its wavelength response.

[0039] This is further illustrated in Table 800 of Figure 8, which explains exemplary operating modes for controlling the activation of the main coupling circuit 214, the additional coupling circuit 322, and the second additional coupling circuit 722 in the directional coupler 700 of Figure 7 to allow selective tuning of the frequency response of the directional coupler 700. As shown in Table 800, when the second additional coupling port switch S7 is activated (closed or "on") and the second additional isolation port switch S8 is deactivated (open or "off"), the directional coupler 700 has the possibility of three (3) additional frequency responses (#4, #5, #6) in modes 4-6, depending on whether the additional coupling port switch S5 and the additional isolation port switch S6 are activated ("on" or "off").

[0040] Similarly, the second additional isolation port switch S8 is configured to be activated (i.e., closed) to couple the second terminal 728 of the second additional coupling line 724 to the isolation output GND, so that the directional coupler 700 and the main coupled RF signal 212 have a different frequency response than when the second additional coupling circuit 722 is not actively included in the directional coupler circuit 702 and coupled to the isolation output GND. When the second additional isolation port switch S8 is activated, the second additional coupling line 724 is EM-coupled to the additional coupling line 224 and / or the main coupling line 216, so that the main coupled RF signal 212 has a different frequency response. The EM coupling of the second additional coupling line 724 to the main coupling line 216 effectively lengthens the main coupling line 216, and thereby lengthens its wavelength response. Coupling the second additional coupling line 724 to the isolation output GND changes the frequency response of the directional coupler 700 to a different frequency response than when the second additional coupling line 724 is coupled to the coupling output CPL_OUT. This is further illustrated in Table 800 in Figure 8. As shown in Table 800, when the second additional isolation port switch S8 is activated (closed or "on") and the second additional coupling port switch S7 is deactivated (open or "off"), the directional coupler 700 has the possibility of three (3) additional frequency responses (#7, #8, #9) in modes 7-9, depending on whether the additional coupling port switch S5 and the additional isolation port switch S6 are activated ("on" or "off").

[0041] Each of the additional and second additional coupling port switches S5, S7 and the additional and second additional isolation port switches S6, S8 can be deactivated (opened or "disconnected") to configure the directional coupler 700 to have the frequency response #1 in the previously described mode 1. The additional switches S1-S4 shown in the directional coupler circuit 702 of FIG7 can be controlled as described above with respect to the directional coupler 300 in FIG3 to control the forward or reverse operation of the directional coupler 700 in FIG7.

[0042] Figure 9 is an exemplary circuit layout 900 illustrating an exemplary layout of the directional coupler circuit 702 in Figure 7, further illustrating the exemplary arrangement of the main coupling line 216, the additional coupling line 224, and the second additional coupling line 724. As illustrated in Figure 9, the main coupling line 216 is arranged as a spiral-shaped metal wire, partially located inside and adjacent to the main transmission line 204. The additional coupling line 224 is arranged as a metal wire partially located inside and adjacent to the main coupling line 216, such that there is mutual inductive coupling between the main coupling line 216 and the additional coupling line 214. The second additional coupling line 724 is arranged as a metal wire partially located inside and adjacent to the additional coupling line 224, such that there is mutual inductive coupling between the second additional coupling line 724 and the additional coupling line 224 and / or the main coupling line 216. The common components between the circuit layout 900 of the directional coupler 700 in Figure 9 and the circuit layout 600 of the directional coupler 300 in Figure 6 are shown by common component numbers. The first end 726 of the second additional coupling line 724 is coupled to the second additional coupling port switch S7, which is coupled to the coupling output CPL_OUT. The second end 728 of the second additional coupling line 724 is coupled to the second additional isolation port switch S8, which is coupled to the isolation output GND.

[0043] Figure 10 is a schematic diagram of another exemplary tunable broadband directional coupler 1000 in a directional coupler circuit 1002 employing up to 'N' additional coupling lines 224(1)-224(N), where 'N' can be any positive integer. The directional coupler 1000 in Figure 10 illustrates that any number of additional coupling lines can be provided to couple the main coupled RF signal 212 to allow selective tuning of the frequency response of the directional coupler 1000. Common elements between the directional coupler 1000 in Figure 10 and the directional coupler 700 in Figure 7 are shown with common element numbers. In this example, each of the additional coupling lines 224(1)-224(N) includes corresponding additional coupling and isolation port switches S5(1)-S5(N), S6(1)-S6(N) to selectively activate the additional coupling lines 224(1)-224(N) in the directional coupler circuit 1002 to control and tune the frequency response of the directional coupler 1000.

[0044] Any of the directional couplers 200, 300, 700, and 1000 in Figures 2, 3, 7, and 10 can be provided as a directional coupler in the RF transmitting circuit 100 in Figure 1.

[0045] Figure 11 illustrates an exemplary wireless communication device 1100 comprising RF elements formed by one or more integrated circuits (ICs) 1102, wherein any IC 1102 may include tunable broadband directional couplers and directional coupler circuits employing one or more additional switchable coupling circuits for controlling frequency response, including but not limited to directional couplers 200, 300, 700, and 1000 in Figures 2, 3, 7, and 10, and directional coupler circuits 202, 302, 702, and 1002 in Figures 2, 3, 7, and 10. As shown in Figure 11, the wireless communication device 1100 includes a transceiver 1104 and a data processor 1106. The data processor 1106 may include memory for storing data and code. The transceiver 1104 includes a transmitter 1108 and a receiver 1110 supporting bidirectional communication. Generally, the wireless communication device 1100 may include any number of transmitters 1108 and / or receivers 1110 for any number of communication systems and frequency bands. All or part of the transceiver 1104 may be implemented on one or more analog ICs, RFICs, mixed-signal ICs, etc.

[0046] Transmitter 1108 or receiver 1110 can be implemented using a superheterodyne architecture or a direct conversion architecture. In a superheterodyne architecture, the signal is converted in multiple stages between the RF and baseband frequencies, for example, from RF to intermediate frequency (IF) in one stage and then from IF to baseband in another stage. In a direct conversion architecture, the signal is converted between the RF and baseband frequencies in one stage. Superheterodyne and direct conversion architectures can use different circuit blocks and / or have different requirements. In the wireless communication device 1100 in Figure 11, transmitter 1108 and receiver 1110 are implemented using a direct conversion architecture.

[0047] In the transmission path, data processor 1106 processes the data to be transmitted and provides I and Q analog output signals to transmitter 1108. In the exemplary wireless communication device 1100, data processor 1106 includes digital-to-analog converters (DACs) 1112(1) and 1112(2) to convert digital signals generated by data processor 1106 into I and Q analog output signals (e.g., I and Q output currents) for further processing.

[0048] Within transmitter 1108, low-pass filters 1114(1) and 1114(2) filter the I and Q analog output signals, respectively, to remove unwanted signals caused by the preceding digital-to-analog conversion. Amplifiers (AMPs) 1116(1) and 1116(2) amplify the signals from low-pass filters 1114(1) and 1114(2), respectively, and provide I and Q baseband signals. Upconverter 1118 upconverts the I and Q baseband signals from transmit (TX) local oscillator (LO) signal generator 1122 via mixers 1122(1) and 1120(2) to provide upconverted signal 1124. Filter 1126 filters upconverted signal 1124 to remove unwanted signals caused by upconversion and noise in the receive band. PA 1128 amplifies the up-converted signal 1124 from filter 1126 to obtain the desired output power level and provide a transmit RF signal. This transmit RF signal is routed through duplexer or switch 1130 and transmitted via antenna 1132.

[0049] In the receiving path, antenna 1132 receives the signal transmitted by the base station and provides a received RF signal, which is routed through duplexer or switch 1130 and provided to low-noise amplifier (LNA) 1134. Duplexer or switch 1130 is designed to operate with a specific receive (RX) and TX duplexer frequency separation, such that the RX signal is isolated from the TX signal. The received RF signal is amplified by LNA 1134 and filtered by filter 1136 to obtain the desired RF input signal. Down-conversion mixers 1138(1) and 1138(2) mix the output of filter 1136 with the I and Q RX LO signals (i.e., LO_I and LO_Q) from RX LO signal generator 1140 to generate I and Q baseband signals. The I and Q fundamental frequency signals are amplified by AMPs 1142(1) and 1142(2) and further filtered by low-pass filters 1144(1) and 1144(2) to obtain I and Q analog input signals, which are provided to data processor 1106. In this example, data processor 1106 includes analog-to-digital converters (ADCs) 1146(1) and 1146(2) to convert the analog input signals into digital signals to be further processed by data processor 1106.

[0050] In the wireless communication device 1100 of Figure 11, a TX LO signal generator 1122 generates I and Q TX LO signals for up-conversion, while an RX LO signal generator 1140 generates I and Q RX LO signals for down-conversion. Each LO signal is a periodic signal with a specific base frequency. A TX phase-locked loop (PLL) circuit 1148 receives timing information from a data processor 1106 and generates control signals for adjusting the frequency and / or phase of the TX LO signals from the TX LO signal generator 1122. Similarly, an RX PLL circuit 1150 receives timing information from a data processor 1106 and generates control signals for adjusting the frequency and / or phase of the RX LO signals from the RX LO signal generator 1140.

[0051] Those skilled in the art will further appreciate that the various descriptive logic blocks, modules, circuits, and algorithms described herein can be implemented as electronic hardware, stored in memory or another computer-readable medium and executed by a processor or other processing device, or a combination of both. As an example, the master and slave devices described herein can be used in any circuit, hardware component, IC, or IC chip. The memory disclosed herein can be of any type and size and can be configured to store any type of information desired. To clearly illustrate this interchangeability, various descriptive elements, blocks, modules, circuits, and steps have been generally described above in their functional form. How such functionality is implemented depends on the specific application, design choices, and / or design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in different ways for each specific application, but such implementation decisions should not be construed as departing from the scope of this document.

[0052] The various descriptive logic blocks, modules, and circuits described herein can be implemented or executed using processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, individual gate or transistor logic, individual hardware components, or any combination thereof, designed to perform the functions described herein. The processor may be a microprocessor, but in alternatives, it may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors coordinated with a DSP core, or any other such configuration).

[0053] The various forms disclosed herein can be embodied in hardware and instructions stored in the hardware, and can reside in, for example, random access memory (RAM), flash memory, read-only memory (ROM), electrically programmable ROM (EPROM), electronically erasable programmable ROM (EEPROM), registers, hard disks, removable disks, CD-ROMs, or any other form of computer-readable media known in the art. Exemplary storage media are coupled to a processor so that the processor can read and write information to / from the storage media. In alternatives, the storage media can be integrated into the processor. The processor and storage media can reside in an ASIC. The ASIC can reside in a remote station. In alternatives, the processor and storage media can reside as separate components in a remote station, base station, or server.

[0054] It should also be noted that the operational steps described in any of the exemplary samples herein are described for the purpose of providing examples and discussion. The described operations may be performed in many different orders other than the order explained. Furthermore, the operations described in a single operational step may actually be performed in multiple different steps. Additionally, one or more operational steps discussed in the exemplary samples may be combined. It should be understood that, as will be apparent to those skilled in the art, many different modifications may be made to the operational steps explained in the flowcharts. Those skilled in the art will also understand that information and signals can be represented using any of a variety of different techniques and arts. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, or any combination thereof.

[0055] The prior description of this application is provided to enable anyone skilled in the art to make or use it. Various modifications to this application will be apparent to those skilled in the art, and the universal principles defined herein can be applied to other variations. Therefore, this application is not intended to be limited to the examples and designs described herein, but should be granted the broadest scope consistent with the principles and novel features disclosed herein.

[0056] Implementation examples are also described in the following numbered formats:

[0057] 1. A directional coupler circuit, comprising: The main transmission line coupled between the input and output ports; Including the main coupling circuit adjacent to the main coupling line of the main transmission line; and Additional coupling circuit, the additional coupling circuit including: This includes an additional coupling line at the first and second ends, which is adjacent to the main coupling line.

[0058] 2. As in Clause 1, the directional coupler circuit, wherein: The input port is configured to couple the received input radio frequency (RF) signal to the main transmission line; and The main coupling line is configured to couple a portion of the power of the input RF signal from the main transmission line to the coupling output as a main coupled RF signal, so as to provide the main coupled RF signal with the main frequency response.

[0059] 3. The directional coupler circuit of clauses 1 to 2, wherein the additional coupling circuit further includes: The additional coupling port switch is coupled to the first end of the additional coupling line and the coupling output.

[0060] 4. The directional coupler circuit of Clause 3, wherein the additional coupling port switch is configured to be activated to couple a first end of the additional coupling line to the coupling output to provide the main coupled RF signal having a second frequency response different from the main frequency response.

[0061] 5. The directional coupler circuit of Clause 4, wherein the additional coupling line is configured to be electromagnetically (EM) coupled to the main coupling line in response to the activation of the additional coupling port switch that couples the first end of the additional coupling line to the coupling output.

[0062] 6. The directional coupler circuit as described in any one of clauses 2 to 5, wherein the additional coupling circuit further comprises: Coupled to the second end of the additional coupling line and the additional isolation port switch of the isolation output.

[0063] 7. The directional coupler circuit of Clause 6, wherein the additional isolation port switch is configured to be activated to couple the second end of the additional coupling line to the isolation output to provide the main coupled RF signal having a third frequency response different from the main frequency response.

[0064] 8. The directional coupler circuit of Clause 7, wherein the additional coupling line is configured to be electromagnetically (EM) coupled to the main coupling line in response to the activation of the additional isolation port switch that couples the second end of the additional coupling line to the isolation output.

[0065] 9. The directional coupler circuit of any one of clauses 1 to 8, wherein the main coupling circuit further comprises: Coupled to the first end of the main coupling line and the first main coupling port switch of the coupled output; Coupled to the second end of the main coupling line and the first main isolation port switch of the isolation output; Coupled to the second end of the main coupling line and the second main coupling port switch of the coupling output; and Coupled to the first end of the main coupling line and the second main isolation port switch of the isolation output.

[0066] 10. As in Clause 9, a directional coupler circuit, wherein: The input port is configured to couple the received input radio frequency (RF) signal to the main transmission line; The main coupling line is configured to couple a portion of the power of the input RF signal from the main transmission line to the main coupled RF signal; The first main coupling port switch is configured to be activated to couple the first end of the main coupling line to the coupling output to provide the main coupled RF signal with a main frequency response; and The first main isolation port switch is configured to be activated to couple the second end of the main coupling line to the isolation output.

[0067] 11. As in Clause 10, a directional coupler circuit, wherein: The second main coupling port switch is configured to be activated to couple the second end of the main coupling line to the coupling output; and The second main isolation port switch is configured to be activated to couple the first end of the main coupling line to the isolation output.

[0068] 12. The directional coupler circuit as described in any one of clauses 10 to 11, wherein the additional coupling circuit further comprises: The additional coupling port switch is coupled to the first end of the additional coupling line and the coupled output; and Coupled to the second end of the additional coupling line and the additional isolation port switch of the isolation output, in: The additional coupling port switch is configured to be deactivated to decouple the first end of the additional coupling line from the coupling output; and The additional isolation port switch is configured to be deactivated to decouple the second end of the additional coupling line from the isolation output.

[0069] 13. The directional coupler circuit of terms 10 to 12, wherein the additional coupling port switch is configured to be activated to couple a first end of the additional coupling line to the coupling output to provide the main coupled RF signal having a second frequency response different from the main frequency response.

[0070] 14. The directional coupler circuit of terms 10 to 13, wherein the additional isolation port switch is configured to be activated to couple the second end of the additional coupling line to the isolation output to provide the main coupled RF signal having a third frequency response different from the main frequency response.

[0071] 15. The directional coupler circuit of Clause 3 further includes a second additional coupling circuit, the second additional coupling circuit comprising: A second additional coupling line includes a first end and a second end, the second additional coupling line being adjacent to the additional coupling line.

[0072] 16. The directional coupler circuit of Clause 15, wherein the second additional coupling circuit further comprises: A second additional coupling port switch is coupled to the first end of the additional coupling line and the coupling port.

[0073] 17. The directional coupler circuit of Clause 16, wherein the second additional coupling port switch is configured to be activated to couple the first end of the second additional coupling line to the coupling output.

[0074] 18. The directional coupler circuit of clauses 15 to 17, wherein the second additional coupling circuit further includes: The second terminal of the second additional coupling line is coupled to the second additional isolation port switch of the isolation port.

[0075] 19. The directional coupler circuit of Clause 18, wherein the second additional isolation port switch is configured to be activated to couple the second end of the second additional coupling line to the isolation output.

[0076] 20. As in clauses 17 to 19, the directional coupler circuit, wherein: The additional coupling port switch is configured to be activated to couple the first end of the additional coupling line to the coupling output; and The second additional coupling port switch is configured to be activated to couple the first end of the second additional coupling line to the coupling output.

[0077] 21. The directional coupler circuit of Clause 19, wherein the additional coupling line includes: Coupled to the second end of the additional coupling line and the additional isolation port switch of the isolation output, in: The additional isolation port switch is configured to be activated to couple the second end of the additional coupling line to the isolation output; and The second additional isolation port switch is configured to be activated to couple the second end of the second additional coupling line to the isolation output.

[0078] 22. The directional coupler circuit as described in any one of clauses 1-21, wherein the directional coupler circuit is integrated into an integrated circuit (IC).

[0079] 23. A method for selectively tuning the frequency response of a directional coupler, comprising: Receive input radio frequency (RF) signals at the input port coupled to the main transmission line; The received input RF signal is transmitted to the output port on this main transmission line; A portion of the power of the input RF signal is coupled as a via RF signal from the main transmission line to a main coupling line adjacent to the main transmission line to provide a main via RF signal with a main frequency response; and An additional coupling line adjacent to the main coupling line is activated to couple a portion of the coupled RF signal to the additional coupling line, thereby providing an additional coupled RF signal with a second frequency response different from that of the main frequency.

[0080] 24. The method of Clause 23, wherein activating the additional coupling line comprises: activating an additional coupling port switch coupled to a first end of the additional coupling line and a coupling port to couple the portion of the coupled RF signal to the additional coupling line to provide the additional coupled RF signal having a second frequency response different from the primary frequency response.

[0081] 25. The method of any one of Clauses 23 to 24, wherein activating the additional coupling line comprises: activating an additional isolation port switch to couple to a second end of the additional coupling line and an isolation output to couple the portion of the coupled RF signal to the additional coupling line to provide the additional coupled RF signal having a third frequency response different from the primary frequency response.

[0082] 26. The method of any one of Clauses 23 to 25, further comprising: disabling the additional coupling line to decouple the portion of the coupled RF signal from the additional coupling line to provide the main coupled RF signal having the main frequency response.

[0083] 27. The method of any one of Clauses 23 to 26, further comprising: activating a second additional coupling line adjacent to the additional coupling line to couple a portion of the additional coupled RF signal to the second additional coupling line to provide a second additional coupled RF signal having a third frequency response different from the primary frequency response and the second frequency response.

[0084] 28. The method of Clause 27 further includes: not activating the additional coupling line.

[0085] 29. The method of any one of Clauses 27 to 28, further comprising: disabling the second additional coupling line to decouple the portion of the additional coupled RF signal from the second additional coupling line to provide the additional primary coupled RF signal having a second frequency response.

[0086] 30. A radio frequency (RF) transmitting circuit, comprising: A power amplifier (PA) circuit, the PA circuit including: PA input, configured to receive input RF signals; and PA output; The PA circuit is configured to amplify the input RF signal into an amplified RF signal at the PA output. Matching network circuit, the matching network circuit includes: The input of the matched network is coupled to the output of this PA; Matching network output; and A directional coupler circuit, comprising: Coupled to the coupler input port of the output of the matching network; Coupler output port; The main transmission line coupled to the input port and the output port of the coupler; Including the main coupling circuit adjacent to the main coupling line of the main transmission line; and Additional coupling circuit, the additional coupling circuit including: Includes an additional coupling line at the first and second ends, which is adjacent to the main transmission line; The additional coupling port switch is coupled to the first end of the additional coupling line and the coupled output; and Coupled to the second end of the additional coupling line and the additional isolation port switch of the isolation output.

[0087] 31. The RF transmitting circuit as described in Clause 30, wherein: The coupler input port is configured to couple the received input RF signal to the main transmission line; and The main coupling line is configured to couple a portion of the power of the input RF signal received from the main transmission line as a main coupled RF signal to the coupling output to provide a main frequency response for the main coupled RF signal.

[0088] 32. The RF transmitting circuit of Clause 31, wherein the additional coupling port switch is configured to be activated to couple the first end of the additional coupling line to the coupling output to provide a second frequency response to the main coupled RF signal that is different from the main frequency response.

[0089] 33. The RF transmitting circuit of any one of Clauses 31 to 32, wherein the additional isolation port switch is configured to be activated to couple a second end of the additional coupling line to the isolation output to provide a third frequency response to the main coupled RF signal, different from the main frequency response.

[0090] 100: Exemplary RF Transmitting Circuit 102: Directional Coupler 104: Power Amplifier (PA) Circuit 106: Input RF signal 108: Output RF signal 110: Matching network 112: Output 114: Main transmission line 115: RF front-end circuit 116: Output Port 118: Main coupling line 120: Coupling Port 122: Coupled RF signal 124: Isolation Port 200: Exemplary Tunable Wideband Directional Coupler 202: Directional Coupler Circuit 204: Main transmission line 206: Input Port 208: Output Port 210: Input RF signal 212: Mainly coupled RF signal 214: Main coupling circuit 216: Main coupling line 218: Coupling Port 220: Isolation Port 222: Additional coupling circuit 224: Additional coupling line 224(1): Additional coupling line 224(N): Additional coupling line 226: First End 228: Second End 230: Additional coupled RF signal 300: Another directional coupler 302: Directional Coupler Circuit 304: Optional RC filter circuit 322: Second additional coupling circuit 400: Table 500: Graphics 502: Frequency Response Curve 504: Frequency Response Curve 506: Frequency Response Curve 600: Exemplary Circuit Layout 602: First end 604: Second end 700: Directional Coupler 702: Directional Coupler Circuit 722: Second Additional Coupling Circuit 724: Second Additional Coupling Line 726: First End 728: Second End 800: Table 900: Exemplary Circuit Layout 1000: Another exemplary tunable broadband directional coupler 1002: Directional Coupler Circuit 1100: Exemplary wireless communication device 1102: Integrated Circuits (ICs) 1104: Transceiver 1106: Data Processor 1108: Transmitter 1110: Receiver 1112(1): Digital-to-Analog Converter (DAC) 1112(2): Digital-to-Analog Converter (DAC) 1114(1): Low-pass filter 1114(2): Low-pass filter 1116(1): Amplifier (AMP) 1116(2): Amplifier (AMP) 1118: Up-converter 1120(1): Mixer 1120(2): Mixer 1122: Mixer 1124: Signal after upsampling 1126: Filter 1128:PA 1130: Duplexer or switch 1132: Antenna 1134: Low-noise amplifier (LNA) 1136: Filter 1138(1): Down-conversion mixer 1138(2): Down-conversion mixer 1140: RX LO signal generator 1142(1):AMP 1142(2):AMP 1144(1): Low-pass filter 1144(2): Low-pass filter 1146(1): Analog-to-digital converter (ADC) 1146(2): Analog-to-digital converter (ADC) 1148: TX Phase-Locked Loop (PLL) Circuit 1150:RX PLL circuit GND: Isolation output S1: Additional switch S2: Additional switch S3: Additional switch S4: Additional switch S5: Additional Coupling Port Switch S6: Additional Isolation Port Switch S7: Second additional switchable coupling port switch S8: Isolation Port Switch

[0091] Domestic storage information (please note in order of storage institution, date, and number) none Overseas storage information (please note in the order of storage country, institution, date, and number) none

Claims

1. A directional coupler circuit, comprising: A main transmission line coupled to an input port and an output port; a main coupling circuit including a main coupling line adjacent to the main transmission line, the main coupling line including a coupling output; and an additional coupling circuit, the additional coupling circuit including: an additional coupling line adjacent to the main coupling line; And an additional coupling port switch, which is connected to the additional coupling line and the coupling output.

2. The directional coupler circuit of claim 1, wherein the directional coupler circuit is integrated into an integrated circuit (IC).

3. The directional coupler circuit as described in request item 1, wherein: The input port is configured to couple the received input radio frequency (RF) signal to the main transmission line; and the main coupling line is configured to couple a portion of the power of the input RF signal from the main transmission line to the coupling output as a main coupled RF signal to provide the main coupled RF signal with a main frequency response.

4. The directional coupler circuit of claim 3, wherein the additional coupling circuit further includes: An additional isolated port switch is coupled to the additional coupling line and an isolated output.

5. The directional coupler circuit of claim 4, wherein the additional isolation port switch is configured to be activated to couple the additional coupling line to the isolation output to provide the main coupled RF signal having a third frequency response different from the main frequency response.

6. The directional coupler circuit of claim 5, wherein the additional coupling line is configured to be electromagnetically (EM) coupled to the main coupling line in response to the activation of the additional isolation port switch that couples the additional coupling line to the isolation output.

7. The directional coupler circuit of claim 1, wherein the additional coupling port switch is configured to be activated to connect the additional coupling line to the coupling output to provide the main coupled RF signal having a second frequency response different from the main frequency response.

8. The directional coupler circuit of claim 7, wherein the additional coupling line is configured to be electromagnetically (EM) coupled to the main coupling line in response to the activation of the additional coupling port switch that connects the additional coupling line to the coupling output.

9. The directional coupler circuit of claim 1, wherein the main coupling circuit further comprises: A first main coupling port switch coupled to the main coupling line and the coupling output; A first main isolation port switch coupled to the main coupling line and an isolated output; A second main coupling port switch is coupled to the main coupling line and the coupling output; and a second main isolation port switch coupled to the main coupling line and the isolation output.

10. The directional coupler circuit as described in claim 9, wherein: The second main coupling port switch is configured to be activated to couple the main coupling line to the coupling output; Furthermore, the second main isolation port switch is configured to be activated to couple the main coupling line to the isolation output.

11. The directional coupler circuit as described in claim 9, wherein: The input port is configured to couple a received input radio frequency (RF) signal to the main transmission line; and the main coupling line is configured to couple a portion of the power of the input RF signal from the main transmission line into a main coupled RF signal; The first main coupling port switch is configured to be activated to couple the main coupling line to the coupling output to provide the main coupled RF signal with a main frequency response; and the first main isolation port switch is configured to be activated to couple the main coupling line to the isolation output.

12. The directional coupler circuit of claim 11, wherein the additional coupling circuit further includes: The additional isolation port switch is coupled to the second end of the additional coupling line and an isolation output, wherein: the additional coupling port switch is configured to be deactivated to disconnect the additional coupling line from the coupling output; and the additional isolation port switch is configured to be deactivated to decouple the additional coupling line from the isolation output.

13. The directional coupler circuit of claim 11, wherein the additional coupling port switch is configured to be activated to connect the additional coupling line to the coupling output to provide the main coupled RF signal having a second frequency response different from the main frequency response.

14. The directional coupler circuit of claim 11, wherein the additional coupling circuit further includes an additional isolation port switch coupled to the additional coupling line and the isolation output, the additional isolation port switch being configured to be activated to couple the additional coupling line to the isolation output to provide the main coupled RF signal having a third frequency response different from the main frequency response.

15. The directional coupler circuit of claim 1, further comprising a second additional coupling circuit, the second additional coupling circuit comprising: A second additional coupling line, which is adjacent to the additional coupling line.

16. The directional coupler circuit of claim 15, wherein the second additional coupling circuit further comprises: A second additional coupling port switch is coupled to the additional coupling line and the coupling port.

17. The directional coupler circuit of claim 16, wherein the second additional coupling port switch is configured to be activated to couple the second additional coupling line to the coupling output.

18. The directional coupler circuit of claim 17, wherein: The additional coupling port switch is configured to be activated to couple the additional coupling line to the coupling output; Furthermore, the second additional coupling port switch is configured to be activated to couple the second additional coupling line to the coupling output.

19. The directional coupler circuit of claim 15, wherein the second additional coupling circuit further comprises: A second additional isolation port switch is coupled to the second additional coupling line and an isolation output.

20. The directional coupler circuit of claim 19, wherein the second additional isolation port switch is configured to be activated to couple the second additional coupling line to the isolation output.

21. The directional coupler circuit of claim 20, wherein the additional coupling line includes: An additional isolation port switch coupled to the additional coupling line and the isolation output, wherein: the additional isolation port switch is configured to be activated to couple the additional coupling line to the isolation output; and the second additional isolation port switch is configured to be activated to couple the second additional coupling line to the isolation output.

22. A radio frequency (RF) transmitting circuit, comprising: A power amplifier (PA) circuit includes: a PA input configured to receive an input RF signal; and a PA output; the PA circuit is configured to amplify the input RF signal into an amplified RF signal at the PA output; a matching network circuit including: a matching network input coupled to the PA output; a matching network output; and a directional coupler circuit including: a coupler input port coupled to the matching network output; a coupler output port; a main transmission line coupled to the coupler input port and the coupler output port; a main coupling circuit including a main coupling line adjacent to the main transmission line; and an additional coupling circuit including: an additional coupling line adjacent to the main transmission line; an additional coupling port switch coupled to the additional coupling line and a coupling output; and an additional isolation port switch coupled to the additional coupling line and an isolation output.

23. The RF transmitting circuit as described in claim 22, wherein: The coupler input port is configured to couple the received input RF signal to the main transmission line; Furthermore, the main coupling line is configured to couple a portion of the power of the input RF signal received from the main transmission line as a main-coupling RF signal to the coupling output, thereby providing a main frequency response to the main-coupling RF signal.

24. The RF transmitting circuit of claim 23, wherein the additional coupling port switch is configured to be activated to couple the additional coupling line to the coupling output to provide a second frequency response to the main coupled RF signal, different from the main frequency response.

25. The RF transmitting circuit of claim 23, wherein the additional isolation port switch is configured to be activated to couple the additional coupling line to the isolation output to provide a third frequency response to the main coupled RF signal, different from the main frequency response.

26. A method for selectively tuning the frequency response of a directional coupler, comprising: Receive an input radio frequency (RF) signal at an input port coupled to a main transmission line; The received input RF signal is transmitted to an output port on the main transmission line; a portion of the power of the input RF signal is coupled from the main transmission line to a main coupling line adjacent to the main transmission line as a coupled RF signal to provide a main coupled RF signal with a main frequency response; and an additional coupling line adjacent to the main coupling line is activated to couple a portion of the coupled RF signal to the additional coupling line to provide an additional coupled RF signal with a second frequency response different from the main frequency response.

27. The method of request item 26, wherein initiating the additional coupling line includes: An additional coupling port switch is activated, coupled to the additional coupling line and a coupling port, to couple the portion of the coupled RF signal to the additional coupling line, so as to provide the additional coupled RF signal having a second frequency response different from the main frequency response.

28. The method of claim 26, wherein activating the additional coupling line includes activating an additional isolation port switch to couple to the additional coupling line and an isolation output to couple the portion of the coupled RF signal to the additional coupling line to provide the additional coupled RF signal with a third frequency response different from the primary frequency response.

29. The method of claim 26, further comprising: The additional coupling line is deactivated to decouple that portion of the coupled RF signal from the additional coupling line, thereby providing the main coupled RF signal with the main frequency response.

30. The method of claim 26, further comprising: A second additional coupling line adjacent to the additional coupling line is activated to couple a portion of the additional coupled RF signal to the second additional coupling line, so as to provide a second additional coupled RF signal having a third frequency response different from the main frequency response and the second frequency response.

31. The method of claim 30 further includes: Do not activate the additional coupling line.

32. The method of claim 30 further includes: The second additional coupling line is deactivated to decouple the portion of the additional coupled RF signal from the second additional coupling line, thereby providing the additional coupled RF signal with the second frequency response.

Images