Built-in transmit / receive switch

Abstract

The TX / RX switch includes a power amplifier (PA), a low noise amplifier (LNA), and an antenna connection. The PA is connected to a PA matching network with a PA network impedance and a common PA-LNA impedance connected in one or more series-parallel combinations in various embodiments in a transmit mode. The LNA is connected to an LNA matching network with an LNA network impedance and an identical common PA-LNA impedance connected in one or more series-parallel combinations in a receive mode. A mode switch may connect the common PA-LNA impedance in different configurations to enable the transmit and receive modes, respectively. In some embodiments, the mode switch may short or open the connection of the PA matching circuit or the LNA matching circuit to the antenna. In some embodiments, the mode switch may also power on or off the PA or the LNA when the switch is in a mode where the respective amplifier is not selected. Therefore, with certain design constraints on the common PA-LNA impedance, combined with different mode switch configurations of the TX / RX switch components for TX or RX mode, the TX / RX switch operates within the design bandwidth without a transmission line embedded within the TX / RX switch circuitry to achieve optimal power transfer to and from the antenna with reduced noise antenna connection.

Description

Technical Field

[0001] The present invention relates to an antenna switch, and more particularly, to an antenna switch that switches a single antenna between a transmission mode and a reception mode in a high-frequency circuit, that is, a TX / RX switch.

Background Art

[0002] A TX / RX switch is used to select / change the connection between a single antenna and a transmitter, a receiver, or a transceiver. For example, in the transmission (TX) mode, the TX / RX switch connects the antenna to a transmitter or a transceiver, that is, a power amplifier (PA) at the output of the transmitter or the transceiver. In the reception mode, the TX / RX switch connects the antenna to the input of a low-noise amplifier (LNA), where the signal from the antenna is amplified and then further processed. By using a TX / RX switch, the same antenna can function as a TX antenna in the transmission mode and as an RX antenna in the reception mode.

[0003] In some embodiments, the TX / RX switch or associated circuitry, or both, also turns power on and off to the PA and LNA as needed. The TX / RX switch is typically a single-pole double-throw (SPDT) switch. In these typical embodiments, the TX / RX switch has a single output / input connected to an antenna, or an antenna connection. The TX / RX switch also has a TX input, typically connected to the PA output, and an RX output, typically connected to the LNA input. In RX / receive mode, the TX / RX switch (or associated circuitry, or both) may power on the LNA, and the TX / RX switch connects the antenna (or antenna in receive mode) to the LNA input. The LNA output is connected to other components in the receiver / transceiver. In TX mode, the TX / RX switch (or associated circuitry, or both) may power on the power amplifier (PA), and the TX / RX switch connects the antenna (or antenna in transmit mode) to the transmitter / transceiver output, for example, through the PA output.

[0004] Generally, antenna signal connections within a TX / RX switch are made through a transmission line. These transmission lines are often quarter-wavelength transmission lines, or λ / 4 transmission lines, where λ is typically the wavelength of the operating frequency. Such λ / 4 transmission lines generally have a characteristic impedance that is close to, or equal to, the antenna's input impedance, i.e., the antenna impedance.

[0005] As an example of prior art for TX / RX switches, see Figure 4 in "A 90-100-GHz 4 x 4 SiGe BiCMOS Ploarimetric Transmit / Receive Phase Array with Simultaneous Receive-Beams Capabilities" by Faith Golcuk et al., IEEE Transactions on Microwave Theory and Techniques, Vol. 61, No. 8, August 2013 (Golcuk). Golcuk shows a schematic and circuit layout of a typical embodiment of the TX / RX switch. In Golcuk's case, the antenna (ANT) is connected to both the TX connection (during transmit mode) and the RX connection (during receive mode). In transmit mode, the antenna is connected to the TX port through a quarter-wavelength (λ / 4) transmission line, the RX port is shorted to ground, and VC=VDD. This, along with a λ / 4 impedance transformer, results in a high impedance to the antenna. In receive mode, the antenna is connected to the RX port via a quarter-wavelength (λ / 4) TX transmission line, the TX port is short-circuited to ground, and VC=0. This results in a high impedance to the antenna due to the λ / 4 impedance transformer.

[0006] As a second example of prior art for TX / RX switches, see Figure 1 in "On the Analysis and Design of Low-Loss Single-Pole Double-Throw W-Band Switches Utilizing Saturated SiGe HBTs" by Robert L. Schmid et al., IEEE Transaction on Microwave Theory and Techniques, Vol. 62, No. 11, November 2014 (Schmid). Schmid presents an alternative embodiment of a conventional quarter-wavelength TX / RX switch implementation using an nFET switching device with a λ / 4 TX transmission line. Here, the "common port" (antenna input) connects the antenna to "switch port 1" via a first quarter-wavelength (λ / 4) transmission line, and "switch port 2" is short-circuited to ground, providing a high impedance to the antenna with a λ / 4 impedance transformer. Alternatively, the circuit connects the antenna to "switch port 2" via a second quarter-wavelength (λ / 4) transmission line, while short-circuiting "switch port 1" to ground. This results in a high impedance to the antenna with a λ / 4 impedance transformer.

[0007] Both Golcuk and Schmid disclose embodiments of a TX / RX switch that connects a first quarter-wavelength (λ / 4) transmission line and shorts the output of a second quarter-wavelength (λ / 4) transmission line to ground. The prior art also discloses embodiments of a TX / RX switch that implements switching of a single quarter-wavelength (λ / 4) transmission line, i.e., one-sided switching. See Alberto Valdes-Garcia et al., "A Fully-Integrated Dual-Polarization 16-Element W-band Phased-Array Transceiver in SiGe BiCMOS", 978-1-4673-6062-3 / 13, 2013 IEEE (Valdes-Garcia).

[0008] These conventional TX / RX switches and TX / RX switches of similar designs experience power loss / dissipation from the PA or LNA, or both, due to the insertion of transmission lines or TX / RX switch components, or both, into one or more of the connections / configurations of the switching circuit. This “insertion loss” degrades performance in transmit mode, receive mode, or both. This performance degradation includes a deterioration of the “noise figure” (NF) in RX mode, and a deterioration of output power level and efficiency in TX mode.

[0009] In many conventional technologies, these insertion losses introduce significant losses in both the LNA and PA connection paths. These insertion losses become more pronounced at higher frequencies (and associated wavelengths λ). Furthermore, in conventional designs, impedance conversion based on quarter-wavelength transmission lines has a limited bandwidth, restricting the bandwidth range of operation for the TX / RX switches.

[0010] Furthermore, quarter-wavelength transmission lines in conventional semiconductor TX / RX switching topologies occupy a large die area, thereby increasing the cost and size of the semiconductor chip.

[0011] There is a need for TX / RX switches with improved insertion loss and wider operating bandwidth that can be effectively integrated into semiconductor circuits with a small form factor. [Overview of the project]

[0012] According to one embodiment of the present invention, the transmit / receive (TX / RX) switch includes a power amplifier (PA) output matching (PA-OM) network (or power matching network (PAM)), a low-noise amplifier (LNA) input matching network (LNA-IM or low-noise amplifier matching (LNAM) network), and a mode switch.

[0013] The PA-OM network has a PA network impedance. In transmit mode, the mode switch connects the common impedance to the PA network impedance, creating a transmit series-parallel combination. Various embodiments of the transmit series-parallel combination match the antenna impedance to the PA-OM's PA-OM (PAM) network output impedance and the PAM-OM's PA-OM (PAM) network input impedance to the power amplifier (PA) output impedance. These transmit series-parallel combinations optimize the power transferred from the PA to the antenna in transmit mode.

[0014] A low-noise amplifier (LNA) input-matched LNA-IM (or LNAM) network has an LNA network impedance (LNAN). In receive mode, a mode switch connects the same common impedance to the LNAN, creating a receive series-parallel combination. Various embodiments of the receive series-parallel combination match the LNA input of the LNA to the LNA-IM output and match the antenna impedance to the LNA-IM input. These receive series-parallel combinations optimize the LNA noise figure and power matching.

[0015] Therefore, the common impedance is common to both LNA-IM (LNAM) and PA-OM networks in the various series-parallel combinations configured by the state of the mode switch, and is used by both LNA-IM (LNAM) and PA-OM networks.

[0016] Embodiments of PA-OM (PAM) and LNA-IM (LNAM) within the TX / RX switch are integrated into the semiconductor. Common impedance eliminates the need to integrate transmission lines within the semiconductor, enabling much smaller embedded semiconductor TX / RX switches.

[0017] Design constraints, design methods, and TX / RX switch operation methods are disclosed.

[0018] Various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings, which are briefly described here. The drawings illustrate various devices, structures, components, circuits, component combinations, and related method steps of the present invention. [Brief explanation of the drawing]

[0019] [Figure 1A] This is a block diagram of a partial TX / RX switch configuration in transmit mode, having a power amplifier (PA) output matching (PA-OM) (PAM) network including a common impedance (CPAp) paired in parallel with the PA network impedance, with the TX / RX switch components shown disconnected to indicate the look-in impedance. [Figure 1B] This is a block diagram of a transmit mode partial TX / RX switch configuration having a power amplifier (PA) output matching network including a common impedance (CPAs) paired in series with the PA network impedance, with the TX / RX switch components shown disconnected to indicate the look-in impedance. [Figure 2A] This is a block diagram of a receiver mode partial TX / RX switch configuration having a low-noise amplifier (LNA) input matching network including an LNA input (including the LNA network impedance) and a common impedance (CPAs / LNAp) paired in parallel, where the TX / RX switch components are shown disconnected to indicate the look-in impedance. [Figure 2B] This is a block diagram of a receiver mode partial TX / RX switch configuration having a low-noise amplifier (LNA) input matching network including LNA inputs (including LNA network impedance) and common impedances (CPAp / LNAs) paired in series, where the TX / RX switch components are shown disconnected to indicate look-in impedance. [Figure 3]This is a block diagram of a single TX / RX switch configuration embodiment with connected components, showing how the mode switch connects the common impedance in series with the LNA input (including the LNA network impedance) in receive mode (mode switch open) and connects the common impedance in parallel with the PA network impedance in transmit mode (mode switch closed). [Figure 4] This is a block diagram of a single TX / RX switch alternative configuration embodiment with connected components, showing how the mode switch connects the common impedance in series with the PA network impedance in transmit mode (mode switch open) and connects the common impedance in parallel with the LNA input (including the LNA network impedance) in receive mode (mode switch closed). [Figure 5A] Figure 3 is a block diagram of one TX / RX switch embodiment, in which the (open) mode switch constitutes the receive mode (RX), and the common impedance is designed to be in series with the LNA input (including the LNA network impedance) for noise and power matching. [Figure 5B] Figure 5A is a circuit diagram of one embodiment of a receive mode series-parallel combination, showing the case where the open-mode switch connects the antenna, common impedance, and LNA input (including LNA network impedance) in series. [Figure 6] Figure 3 is a block diagram of one TX / RX switch embodiment, in which the mode switch configures the transmit mode (TX), the closed mode switch shorts the LNA input to ground, and the common impedance is connected in parallel with the PA network impedance. [Figure 7] Figure 4 is a block diagram of an alternative TX / RX switch embodiment in which the (closed) mode switch shorts the PA (Network Impedance) output to ground and connects the common impedance in parallel with the LNA input (including the LNA network impedance) to configure the receive mode. [Figure 8]The (ON) mode switch constitutes a transmission mode by connecting a common impedance in series with the PA circuit network impedance, and the LNA is powered off. It is a block diagram of the TX / RX switch embodiment shown in FIG. 4. [Figure 9] It is a block diagram of an exemplary TX / RX switch incorporated on a substrate, such as a semiconductor substrate, without the need to include transmission lines on the substrate. [Figure 10] It is a flowchart of the switching process using the TX / RX switch.

Best Mode for Carrying Out the Invention

[0020] Embodiments of the present invention are not limited to the exemplary methods, apparatuses, structures, systems, and devices disclosed herein, and it should be understood that they are widely applicable to other alternative and broader methods, apparatuses, structures, systems, and devices that will be apparent to those skilled in the art given the present disclosure.

[0021] Furthermore, it should be understood that the various components, structures, or regions shown in the accompanying drawings, or combinations thereof, are not drawn to scale, and one or more components, circuits, structures, or regions of a generally used type, or combinations thereof, may not be explicitly shown in the drawings. This does not imply that components, circuits, structures, or regions not explicitly shown are omitted from the actual device.

[0022] Furthermore, when the description does not necessarily focus on some elements, such elements may be omitted from view for clarity or simplicity or both. Furthermore, the same or similar reference numbers used throughout the drawings are used to indicate the same or similar features, elements, components, or structures, and thus detailed descriptions of the same or similar features, elements, or structures are not repeated for each of the drawings.

[0023] Semiconductor devices, structures, and methods disclosed in accordance with embodiments of the present invention may be used in applications, hardware, communications, or electronic systems. Suitable hardware and systems for implementing embodiments of the present invention may include, but are not limited to, personal computers, communication networks, e-commerce systems, portable communication devices (e.g., cell phones and smartphones), solid-state media storage devices, expert and artificial intelligence systems, functional circuits, neural networks, and the like. Systems and hardware incorporating semiconductor devices and structures constitute the intended embodiments of the present invention.

[0024] In this specification, “height” refers to the vertical size of an element (e.g., a layer, trench, hole, opening, etc.) in a section or front view, measured from the bottom to the top of the element and / or relative to the surface on which the element is placed.

[0025] Conversely, "depth" refers to the vertical size of an element (e.g., a layer, trench, hole, opening, etc.) in a section or front view, measured from the top to the bottom of the element. Terms such as "thick," "thickness," "thin," or their derivatives may be used instead of "height" when indicated.

[0026] In this specification, "lateral," "lateral side," "side," and "lateral surface" refer to the side surface of an element (e.g., a layer, opening, etc.) such as the left or right side of a drawing.

[0027] In this specification, “width” or “length” refers to the size of an element in a drawing (e.g., a layer, trench, hole, opening, etc.) measured from one side of the element to the opposite surface. Terms such as “thick,” “thickness,” “thin,” or their derivatives may be used instead of “width” or “length” when indicated.

[0028] In this specification, “upper,” “lower,” “right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” and their derivatives refer to the disclosed structures and methods as oriented in the drawings / figures. For example, in this specification, “vertical” refers to a direction perpendicular to the top surface of the substrate in the front view, and “horizontal” refers to a direction parallel to the top surface of the substrate in the front view.

[0029] In this specification, unless otherwise specified, terms such as “on,” “overlying,” “atop,” “on top,” “positioned on,” and “positioned atop” mean that the first element is on the second element and that intervening elements may exist between the first and second elements. In this specification, unless otherwise specified, terms such as “on,” “overlying,” “atop,” “on top,” “positioned on,” “positioned atop,” and “disposed on,” or the terms “in contact” or “direct contact,” mean that the first and second elements are connected without any intervening elements present between the first and second elements, such as an intermediate conductive layer, intermediate insulating layer, or intermediate semiconductor layer.

[0030] It should be understood that these terms may be affected by the orientation of the device described. For example, if the device is rotated upside down, the meaning of these descriptions may change, but the descriptions remain valid as they describe the relative relationships between the features of the invention.

[0031] Embodiments of the present invention are incorporated on / within a semiconductor chip, for example, on the surface of a semiconductor substrate, and / or within the substrate, by well-known semiconductor manufacturing techniques.

[0032] Embodiments of a TX / RX switch include a power amplifier (PA), a low-noise amplifier (LNA), a power amplifier (PA) output matching (PA-OM) network, a low-noise amplifier (LNA) input matching network (LNA-IM), a mode switch, and antenna connections.

[0033] The PA has a PA output with PA output impedance. The PA output is connected to the PA-OM network input. The PA-OM network has a PA-OM network output connected to an antenna connection in one of one or more different switchable configurations. The PA-OM network has PA network impedance and common impedance. The PA network impedance and common impedance can be connected in different transmit series-parallel combinations by a mode switch.

[0034] The LNA has an LNA input with an LNA input impedance. The LNA input is connected to an LNA input matching network (LNA-IM) output. The LNA-IM network input is connected to an antenna connection in one of one or more different switchable configurations by a mode switch. The LNA-IM network has an LNA network impedance. The LNA network impedance and the common impedance can be connected in different receiver series-parallel combinations by a mode switch in different embodiments.

[0035] The mode switch uses / configures the same common impedance when configuring the PA network impedance in transmit mode and when configuring the LNA-IM network in receive mode.

[0036] Indeed, depending on whether the mode switch is in transmit mode / position or receive mode / position, different configurations of the mode switch may connect a common impedance in one or more series / parallel combinations with the PA network impedance or LAN network impedance or both. In some embodiments, the mode switch may also be able to power on or off the PA or LNA.

[0037] Therefore, along with specific design constraints regarding PA network impedance, common impedance, and LNA network impedance, combined with one or more different mode-switch configurations of the TX / RX switch components, the TX / RX switch operates within the design bandwidth to optimally transfer power to and from the antenna. Furthermore, the TX / RX switch can be integrated within a semiconductor chip without the transmission line being incorporated with the TX / RX switch circuit. In either TX mode or RX mode, maximum power is transferred to and from the antenna.

[0038] As described below, common impedance can have various configurations and can have various values ​​determined by the mode switch configuration, TX / RX switch circuit design, PA network impedance values, and LAN network impedance.

[0039] Please refer to the diagram here.

[0040] Figure 1A is a block diagram of a partial TX / RX switch configuration embodiment 100 in transmit mode, having a power amplifier (PA) 120 output matching (PA-OM) network 125 / 125P including a common PA-LNA impedance (CPA / CPAp) 140 (127P) connected in parallel with the PA network impedance (PAN) 130, with the TX / RX switch components 120 / 125 / 125P / 110 / 105 / 140 shown disconnected to indicate look-in impedances 122 / 135 / 132 / 134 / 115.

[0041] Figure 1B is a block diagram of an alternative embodiment 150 of a partial TX / RX switch configuration in transmit mode, having a power amplifier (PA) 120 matching network (PA-OM) 125 / 125S including a common PA-LNA impedance (CPA / CPAs) 140 paired in series with a PA network impedance (PAN) 130, with the TX / RX switch components 120 / 125 / 125S / 110 / 105 / 140 disconnected to show look-in impedances 122 / 135 / 132 / 134 / 115.

[0042] In some embodiments, the antenna 110 has an operating frequency (the frequency at which the antenna 110 is excited), a transmission line (not shown) connecting the antenna 110 to the antenna connection 111, a power amplifier output matching network 125 / 125P / 125S, or other elements, or a combination thereof, which may vary with the look-in or input impedance (Anti) 115. In some embodiments, the transmission line connects the antenna 110 input (Anti) 115 to the power amplifier output matching network 125 / 125P / 125S output (PA-OMo / PAMo) 134 through the antenna connection 111.

[0043] In some embodiments, the look-in output impedance (PA-OMo) 134 of the power amplifier output matching network (PA-OM) 125 output (PA-OMo) 134 matches (or is identical) to the antenna 110 input impedance (Anti) 115 at the system operating frequency (e.g., the resonant frequency of antenna 110). Under this impedance matching condition, assuming that the impedances match at other circuit locations, as described below, the maximum power is transferred from PA 120 to antenna 110 in the transmit modes shown in Figures 1A and 1B.

[0044] In some embodiments, components including PA120, PA output matching network, PA-OM125, and antenna 110 are connected to common connection 105 or ground 105 by known techniques.

[0045] The power amplifier (PA) 120 output matching (PA-OM) network 125 / 125P / 125S includes a PA network impedance (PAN) 130. The PA-OM network 125 / 125P / 125S has a PA-OM network input (PA-OMi) 135 having a PA output matching network input impedance (PA-OMi) 135, and a PA output matching network output 134 having a PA network output impedance (PA-OMo) 134.

[0046] In some embodiments, the PA output matching network input 135 is the same connection as the parallel connection across the PAN 130. The PA-OM input (PAMi / PA-OMi) 135 interfaces with the PA output connection (PAo) 122. The PA120 output connection 122 has a PA120 output impedance (PAo) 122.

[0047] PA output matching network 125 / 125P / 125S output (PA-OMo) 134 is connected to antenna 110 input (Anti) 115 via antenna connection 111 and ground connection 105.

[0048] In some embodiments, in transmit mode, the antenna 110 input impedance (Anti) 115 (or external transmission line (not shown) impedance, or both) is matched to the PA output matching network 125 / 125P / 125S output impedance (PA-OMo) 134 by connecting the antenna 110 input 115 to the antenna connection 111. Furthermore, the PA-OM network 125 / 125P / 125S input impedance (PA-OMi) 135 is matched to the PA 120 output connection impedance (PAo) 122. In this way, in transmit mode, the output 122 of PA 120 transfers maximum power from PA 120 to the PA-matched output network (PA-OM) 125 / 125P / 125S and then to antenna 110. A mode switch configures a common PA-LNA impedance (CPAp / CPAs) 140 to achieve this matching. See the description below.

[0049] One way to view PA-LNA impedance (CPAp / CPAs) 140 is as a circuit or component possessing the physical properties of impedance. Therefore, without loss of generality, a reference to connecting impedances, etc., means connecting a circuit / component to this impedance characteristic.

[0050] In the embodiment 100 shown in Figure 1A, the PA-OMp 125 / 125P includes a PA network impedance (PAN) 130 connected to a common PA-LNA impedance (CPAp) 140 in a parallel combination via a common parallel PA impedance connection (PAMc) 127P. In this embodiment, in transmit mode, the PA output (PAo) 122, the PA output matching network (PA-OM) 125 / 125P, and the antenna 110 are connected in parallel with their respective impedance matching as described above, enabling maximum power transfer from PA 120 to antenna 110.

[0051] In the alternative embodiment 150 shown in Figure 1B, the PA-OMs 125 / 125S include a PA network impedance (PAN) 130 connected to a common PA-LNA impedance (CPAs) 140 in a series combination using common series PA impedance connections (PA-OMs) 127S.

[0052] As shown in these embodiments 100 / 150, the PA-OM125 may include a PAN130 connected to a common PA-LNA impedance 140 in series, parallel, or series-parallel combination. The focus of such connections / combinations is to match the impedances at the inputs and outputs of the PA-OM125 to enable maximum power transfer or other operational efficiency, or both. For example, in transmit mode, the following impedance pairs should be matched: PAo122 matched to PA-OMi135 and PA-OMo134 matched to Anti115. Note that for such impedance matching, maximum power transfer is performed within the TX / RX switch without requiring transmission lines within the TX / RX switch circuit.

[0053] Additional design considerations include other series-parallel combinations of the common PA-LNA impedance 140 via mode switching, as described below.

[0054] The common component 140 (CPAp, CPAs) is the same common impedance used with both PA120 and LNA220 in both transmit and receive modes, although the design value of the common impedance may vary with the configuration. See Figure 2. The common impedance 140 (CPAp / LNAs, CPAs / LNAp) is designed so that different mode switch positions configure the common impedance 140 in a receive mode series-parallel combination in receive mode and in a transmit mode series-parallel combination in transmit mode. The value of the common impedance 140 is determined to allow for maximizing power transfer to and from the antenna with a high signal-to-noise ratio over a wide bandwidth. See further explanation below.

[0055] In embodiments 100 / 150, in transmit mode, the PA120 includes transistors T1 and T2, and it should be noted that this indicates a PA120 having a differential back-end, for example, a "push-pull" configuration. The PA120 may also be configured with a single-end back-end output stage. Furthermore, as is well known, the PA signal may be applied to the base connections of transistors T1 and T2. Other well-known PA120 configurations are conceivable.

[0056] Figure 2A is a block diagram of a partial TX / RX switch configuration 200 in a receiving mode embodiment, including a low-noise amplifier (LNA) 220 input matching network LNA-IMp225 / 225P, which includes a common PA-LNA impedance CPAs / LNA140 paired in parallel with the LNA network impedance LNAN230, and the TX / RX switch components are shown disconnected to show the look-in impedances 231 / 235 / 232 / 234 / 115.

[0057] Figure 2B is a block diagram of a partial TX / RX switch configuration 250 in a receiver mode alternative embodiment having a low-noise amplifier (LNA) 220 input matching network (LNA-IMS) 225 / 225S including a common PA-LNA impedance (CPAp / LNA) 140. In this embodiment, the common PA-LNA impedance (CPAp / LNAs) 140 is combined in series with the LNA network impedance (LNAN) 230. The TX / RX switch components are shown disconnected to show the look-in impedances 231 / 235 / 232 / 234 / 115.

[0058] In some embodiments, the LNA network impedance (LNAN) 230 is omitted.

[0059] It should be noted that LNA220 indicates that transistors T3 and T4 are in a differential input configuration. LNA220 can also be configured with a single transistor, for example, a single T3 input stage. Other known LNA220 configurations are conceivable. In some embodiments, LNA220 has an input stage impedance 221 that can affect the LNA220 input impedance (LNAi) 231.

[0060] In receive mode, power from antenna 110 is transferred to LNA220 input (LNAi) 231 via low-noise amplifier (LNA) 220 input matching network (LNA-IM) 225 / 225S / 225P.

[0061] As described above, in Embodiment 200, the LNA network impedance (LNAN) 230 is connected in a receive-parallel combination with the common PA-LNA impedance (LNAp / CPAs) 140. Furthermore, in Embodiment 250, the LNA network impedance (LNAN) 230 is connected in series with the common PA-LNA impedance (CPAp / LNA) 140 in a receive-series combination. Other series-parallel combinations within the LNA220 input matching network (LNA-IM) 225 / 225S / 225P are envisioned to enable maximum power transfer, improved noise figure, and efficient TX / RX switching operation in each of the one or more mode-switch combinations described below.

[0062] Figure 3 is a block diagram of one TX / RX switch configuration embodiment 300 having a mode switch 350 in the open position in a receive mode configuration with connected components. In receive mode (RX), the mode switch 350 can connect the LNA network impedance (LNAN230) and the common PA-LNA impedance CPAp140 in a receive mode series-parallel combination 325.

[0063] For example, in the closed position, mode switch 350 connects the common PA-LNA impedance (CPAp) 140 and PA network impedance (PAN) 130 in parallel in a transmit series-parallel combination 325 in transmit mode (TX). Thus, by designing the common PA-LNA (CPAp / LNAs) impedance 140 within the specific constraints determined by the series-parallel combination and other configurations created by the mode switch 350 configuration, the input impedance or output impedance of PA-OM125 and LNA-IM225, or both, can be changed in their respective RX and TX modes to optimize power transmission to and from antenna 110 at antenna connection 111 without requiring a transmission line in the TX / RX switch.

[0064] For example, as shown in Embodiment 300 of Figure 3, the mode switch is shown in the open position, in this Embodiment 300, the open position places this Embodiment of the TX / RX switch 300 into receive mode. In this configuration, the mode switch 350 connects the common PA-LNA impedance 140 in a receive series-parallel combination 325, which connects the common impedance 140 in series with the LNA 220 network impedance (LNAN) 230.

[0065] In some embodiments, the digital control / circuit controlling the mode switch 350 also controls a switching (not shown) that disconnects or cuts off power to PA120 (and optionally connects power to LNA220). When PA120 is powered off and LNA220 is powered on, transistor T3 operates, and in this embodiment of the receiver series-parallel combination 325, through the ON transistor T3, combines the common impedance 140 in series with the LNAN230 and the LNA220 input impedance (LNAi) 231 (relative to the input stage impedance 221). Thus, power from antenna connection 111 passes through a voltage divider circuit including impedances 140, 230, and 231 connected in series.

[0066] In some embodiments, once a common PA-LNA impedance 140 that satisfies the requirements disclosed herein is determined, the LNAN 230, input stage impedance 221, transistor T3, or transistor T4, or a combination thereof, may be selected to reduce noise (lower signal-to-noise ratio) and match impedances for maximum power transfer.

[0067] Alternatively, closing mode switch 350 places the TX / RX switch 300 into transmit mode. Closing mode switch 350 shorts the input to LNA 220 to ground. In this mode switch 350 position, the series-parallel combination 325 is a transmit series-parallel combination 325 with a common impedance (CPAp) 140 connected in parallel with the PA network impedance (PAN) 130. In this transmit mode, the PA matching network (PA-OM) 125, having an input impedance (PA-OMi) 135 and an output impedance (PA-OMo) 134, matches the impedance of the PA output (PAo) 122 by connecting it to the input PA-OMi 135 and matches it by connecting (PA-OMo) 134 to the antenna 110 input 115. Thus, by correctly designing the common PA-LNA impedance (CPAp) 140, maximum power is supplied from PA 120 to antenna 110 connection 111 within the operating bandwidth.

[0068] Figure 4 is a block diagram of an alternative embodiment 400 of a TX / RX switch configuration having components connected to a mode switch 450 in an alternative location within the configuration 400.

[0069] In this embodiment, when the mode switch 450 is in the closed position, the TX / RX switch 400 is in receive mode. See the description in Figure 7. When the mode switch 450 is in the open position, the TX / RX switch 400 is in transmit mode. See the description in Figure 8.

[0070] For example, in some embodiments of the receive mode, power is switched off for PA120 and switched on for LNA220, and transistor T3 operates. In this receive mode configuration, the closed mode switch 450 shorts PAN130 to ground. The closed mode switch 450 also connects the common PA-LNA impedance (CPAs) 140 in parallel with antenna 110 and in parallel with a series combination of LNA network impedance (LNAN) 230 and input impedance LNAi231 (relative to input stage impedance 221). For example, in this embodiment of the receive mode, the configuration of the mode switch 450 creates a receive series-parallel combination 425 that connects CPAs 140 in parallel with a series connection of LNAN230 and input impedance LNAi231.

[0071] When the mode switch 450 is in the open position, the TX / RX switch 400 is in transmit mode. For example, in some embodiments, the LNA 220 is powered off and the PA 120 is powered on. The voltage across the PAN 130 generates an oscillating current in the antenna 110 through the common impedance CPAs 140.

[0072] Figure 5A is a block diagram of one TX / RX switch embodiment 300 shown in Figure 3, which has a mode switch 350 (in the open position) that constitutes the receiving mode (RX), and a common PA-LNA impedance (CPAp) 140 is designed for the receiving mode series-parallel combination 325. Figure 5B is a circuit diagram of the receiving mode series-parallel combination 325, in which the common PA-LNA impedance (CPAp) 140, LNA network impedance (LNAN) 230, LNA 220 input impedance (LNAi) 231, and antenna 110 are connected in series.

[0073] In some embodiments, PA is turned OFF.

[0074] Figure 6 is a block diagram of one TX / RX switch embodiment 600, which is a simplified version of the circuit shown in Figure 3 for the transmit mode. In this embodiment, the mode switch 350 is in the closed position, configuring the TX / RX switch to transmit mode (TX), and the components are designed for transmit mode and connected in a series-parallel combination 325.

[0075] The closed mode switch 350 shorts the LNAN230 and input impedance LNAi231 to ground. In some embodiments, LNA220 is also powered off. The closed mode switch connects the PAM network 125, PA output (PAo) 122, and antenna 110 in parallel. Thus, in this transmit mode, the transmit series-parallel combination is the PA network (PAN) impedance 130 connected in parallel with the common PA-LNA impedance (CPAp) 140, which are also connected in parallel with the PA120 output (PAo) 122 and antenna 110.

[0076] Figure 7 is a block diagram of an alternative TX / RX switch embodiment 700 shown in Figure 4, which has a closed-position mode switch 450 that constitutes the receive mode (RX), and the components are designed and configured for a series-parallel combination of receive modes 425 / 725.

[0077] In this receiving mode series-parallel combination 425 / 725, PA120 may be powered off, and the PA120 output (PAo) 122 is shorted to ground. Input impedances LNAi231, LNAN230, and antenna 110 are connected in series and in parallel across the common impedance CPAs 140.

[0078] Figure 8 is a block diagram of the TX / RX switch embodiment 800 shown in Figure 4, which has a mode switch 450 in the open position. The mode switch 450 constitutes the transmit mode (TX), and its components are designed for a transmit mode series-parallel combination 825, which is comprised of the transmit mode series-parallel combination 825. The LNA 220 can be powered off. The antenna 110 common impedance CPAs 140 and the PA network impedance (PAN) 130 are connected in series in this transmit mode embodiment.

[0079] Figure 9 is a block diagram of an exemplary TX / RX switch 900 incorporated on a substrate 990, for example, a semiconductor substrate 990. The TX / RX switch uses a minimal footprint surface 991 on the surface of the substrate 990.

[0080] The substrate 990 may be any compatible substrate well known in the semiconductor industry, such as silicon dioxide (SiO2). The components PA120, PA-OM / PAM125, LNA220, LNA-IM / LNAM225, and mode switch 950 are incorporated into / on the substrate in a well-known manner.

[0081] In one embodiment, the power module 925 includes PA120 and PA-OM network 125, and the LNA module 975 includes LNA220 and LNA-IM225. The mode switch 950 may be connected in any of the disclosed modes and configurations. Other configurations that conform to the concepts disclosed herein are conceivable.

[0082] In some embodiments, a transmission line is not required to match the impedance between the antenna 110 and the power amplifier module 925, or between the antenna 110 and the LNA module 975, thus minimizing the footprint surface area 991. A common impedance 140 switch 950 enables a wire connection between the antenna connection 111 and the PA network impedance (PAN) 130 (PAN connection 112). Furthermore, a common impedance 140 switch 950 enables a wire connection between the antenna connection 111 and the LNA network impedance (LNAN) 230 (LNAN connection 229).

[0083] The distance between antenna connection 111 and PAN connection 112 is the PAN connection length 112L. The distance between antenna connection 111 and LNA connection 229 is the LNA connection length 229L. The PAN length 112L and the LNA connection length 229L are each less than or equal to λ / 4, i.e., one-quarter of the wavelength λ in the substrate at the antenna operating frequency.

[0084] In some embodiments, the common component CPAp / CPAs 140 has a specific selected impedance value, as defined by the design conditions described above. Furthermore, as previously stated, the common component 140 is configured by the mode switch 950 into a series-parallel receive and transmit configuration, respectively, to maximize power transfer and minimize noise in the receive and transmit modes. Therefore, it is not necessary to have a transmission line on or within the board 990 to achieve impedance matching of the components. As a result, the size of the chip 950 can be significantly reduced.

[0085] It should be noted that the connection between the antenna connection 111 on the board 990 and the antenna 110 is typically a transmission line 910. However, the transmission line 910 is outside the TX / RX switch embodiment 900 and does not use any space within the board 990 / chip.

[0086] Figure 10 is a flowchart of a switching process 1000 using one of the disclosed TX / RX switch embodiments.

[0087] The switching process 1000 begins in step 1005, when a first mode, namely receive mode or transmit mode, is selected by the mode switch 350 / 450 / 950.

[0088] Step 1010 is an optional step to power off amplifiers not used in the selected mode. For example, PA120 is powered off in receive mode, and LNA220 is powered off in transmit mode. Amplifiers in use can also be powered on by the mode switch.

[0089] In step 1015, the mode switch 350 / 450 / 950 configures a common impedance 140 for the series-parallel combinations corresponding to the selected mode. For example, in receive mode, the receive series-parallel combination uses a common PA-LNA impedance, e.g., 140, and in transmit mode, the transmit series-parallel combination uses the same common PA-LNA impedance, e.g., 140.

[0090] In step 1020, the mode selection performed by the mode switch 350 / 450 / 950 is changed. The first mode, for example, the selected transmit mode, is deselected, and the second mode, for example, the receive mode, is selected. The mode change is achieved by changing the position of the mode switch. In some embodiments, the mode switch 350 / 450 / 950 is a switching transistor such as a bipolar transistor or a metal oxide semiconductor transistor.

[0091] In some embodiments, the mode switch 350 / 450 / 950 is designed to be "off" in one of the selected modes, and as a result, power to the mode switch 350 / 450 / 950 is applied only in one of the selected modes. In this way, power is saved because the mode switch 350 / 450 / 950 is only required / used in one of the (transmit or receive) modes.

[0092] Step 1025 is an optional step in which the amplifiers 120 / 220 used in the deselected mode are powered off and the amplifiers 120 / 220 used in the last selected mode are powered on.

[0093] In step 1030, the mode switches 350 / 450 / 950 configure the same common impedance 140 into a series-parallel combination corresponding to the newly / last selected mode. For example, if the newly / last selected mode is the receive mode, the receive series-parallel combination is configured by the mode switches 350 / 450 / 950, the PA120 is optionally powered off, and the transmit series-parallel combination is deconfigured.

[0094] Since no additional λ / 4 transmission line is required for switching between RX and TX modes, both the noise figure (NF) in the receiving mode (RX) and the PA compression point (i.e., output power) in the transmitting mode (TX) are improved. Therefore, by using the present invention, the extra insertion loss added by the λ / 4 transmission line used in the prior art is avoided, and thus the NF and output power are not reduced.

[0095] For example, conventional mode switching relies on using a switch to short-circuit a λ / 4 transmission line to ground or open the line to a high-impedance state. Such conversions operate and are limited to specific design frequencies. However, the present invention avoids these limitations and operates over a wide bandwidth.

[0096] The descriptions of various embodiments of the present invention are presented for illustrative purposes only and are not exhaustive, nor are they limited to the embodiments disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope of the embodiments described. The terms used herein have been chosen to best describe the principles of the embodiments, the practical applications or technical improvements that surpass the art available on the market, or to enable those skilled in the art to understand the embodiments disclosed herein. Devices, components, elements, features, apparatus, systems, structures, techniques, and methods described in different terms that perform substantially the same function, function substantially similarly, have substantially the same use, and / or perform similar steps are contemplated as embodiments of the present invention.

Claims

1. A transmit / receive (TX / RX) switch, Common PA-LNA impedance and A PA-OM (PA-OM) power amplifier (PA) network having a PA network impedance, the PA-OM network having a PA-OM network output having a PA-OM network output impedance and a PA-OM network input having a PA-OM network input impedance, A low-noise amplifier (LNA) network having LNA input matching (LNA-IM) impedance, the LNA-IM network having an LNA-IM network input having an LNA-IM network input impedance and an LNA-IM matching network output having an LNA-IM matching network output impedance, A mode switch connects the aforementioned common PA-LNA impedance either in a series or parallel configuration in receive mode, and either in a series or parallel configuration in transmit mode. Equipped with, In the receiving mode, the mode switch configures the common PA-LNA impedance together with the LNA network impedance in the receiving series or receiving parallel combination, so that the LNA-IM network output impedance matches the LNA input impedance of the low-noise amplifier (LNA), and the LNA-IM input impedance matches the antenna impedance, thus reducing the LNA noise figure. In the transmission mode, the mode switch configures the PA network impedance together with the common PA-LNA impedance in the series or parallel transmission combination, so that the PA network output impedance matches the antenna impedance, the PA network input impedance matches the PA output impedance of the power amplifier (PA), and optimizes power transfer from the PA to the antenna. TX / RX switch.

2. The TX / RX switch according to claim 1, wherein the common PA-LNA impedance is connected in parallel with the PA network impedance.

3. The TX / RX switch according to claim 1, wherein the common PA-LNA impedance is connected in series with the PA network impedance.

4. The TX / RX switch according to claim 1, wherein the mode switch shorts the LNA network impedance to ground in the transmit mode.

5. The TX / RX switch according to claim 1, wherein the mode switch turns off power to the LNA in the transmit mode.

6. The TX / RX switch according to claim 1, wherein the mode switch shorts the PA network impedance to ground in the receiving mode.

7. The TX / RX switch according to claim 1, wherein the mode switch turns off power to the PA in the receiving mode.

8. The TX / RX switch according to claim 1, wherein the mode switch connects the PA network impedance, the common PA-LNA impedance, and the antenna connection in parallel in the transmit mode.

9. The TX / RX switch according to claim 1, wherein the mode switch connects the antenna connection, the common PA-LNA impedance, and the LNA network impedance in series.

10. The TX / RX switch according to claim 1, wherein the mode switch connects the antenna connection and the common PA-LNA impedance in parallel with the LNA network impedance.

11. The TX / RX switch according to claim 10, wherein the mode switch turns off power to the PA in the receiving mode.

12. A transmit / receive (TX / RX) switch integrated into a semiconductor chip, Semiconductor substrate and Antenna connection and, Common PA-LNA impedance and The power amplifier (PA) portion disposed on the aforementioned substrate, PA with PA output impedance, A power amplifier (PA) output matching (PA-OM) network having PA network impedance, the PA-OM network having a PA-OM network output having PA-OM network output impedance and a PA-OM network input having PA-OM network input impedance. The PA portion comprises, The low-noise amplifier (LNA) portion incorporated on the aforementioned substrate, A low-noise amplifier (LNA) having an LNA input, wherein the LNA input has an LNA input impedance, and the LNA and A low-noise amplifier (LNA) input matching (LNA-IM) network having LNA network impedance, the LNA-IM network having an LNA-IM network input having an LNA-IM network input impedance and an LNA-IM matching network output having an LNA-IM matching network output impedance. The LNA portion comprises, A mode switch connects the aforementioned common PA-LNA impedance either in a series or parallel configuration in receive mode, and either in a series or parallel configuration in transmit mode. Equipped with, In the receiving mode, the mode switch configures the common PA-LNA impedance together with the LNA network impedance in the receiving series or receiving parallel combination, so that the LNA-IM network output impedance matches the LNA input impedance of the low-noise amplifier (LNA), and the LNA-IM input impedance matches the antenna impedance, thus reducing the LNA noise figure. In the transmission mode, the mode switch configures the PA network impedance together with the common PA-LNA impedance in the series or parallel transmission combination, so that the PA network output impedance matches the antenna impedance, the PA network input impedance matches the PA output impedance of the power amplifier (PA), and the power transfer from the PA to the antenna connection is optimized. switch.

13. The switch according to claim 12, wherein the LNA connection length is the length of the connection between the antenna connection and the LNA connection, the PAN connection length is the length of the connection between the antenna connection and the PAN connection, and the LNA connection length and the PAN connection length are each less than one-quarter of the wavelength of the antenna operating frequency within the substrate.

14. The switch according to claim 12, wherein the transmission line connects the antenna connection to the antenna.

15. The switch according to claim 12, wherein the PA is powered off in the receiving mode.

16. The switch according to claim 12, wherein the LNA is powered off in the transmission mode.

17. The switch according to claim 12, wherein the mode switch uses energy only when the switch is in either the transmit mode or the receive mode, but not both.

18. The switch according to claim 12, wherein the mode switch shorts the LNA network impedance to ground in the transmission mode.

19. The switch according to claim 12, wherein the mode switch short-circuits the PA network impedance to ground in the receiving mode.

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