Compact broadband frequency insensitive rectifier for wireless power supply Internet of Things equipment

Abstract

The invention provides a compact broadband frequency insensitive rectifier for collecting electromagnetic energy in an environment, and aims to face the field of wireless power supply Internet of Things equipment. The invention finds that the double-branch LC series-parallel structure has a key characteristic that the impedance is insensitive to frequency change. By fully utilizing the characteristic, a simple matching network is designed to realize broadband performance. Through a simulation and measurement combined method, the operation effectiveness of the proposed topological structure is verified, and the design of the broadband rectification circuit is successfully realized. The rectification circuits of three different matching networks are compared, and the optimal circuit is determined. Under the input of 8 dBm and the load of 1.2 k omega, the peak power conversion efficiency of the rectifier reaches 74.75%. And the efficiency is kept above 60% at the relative bandwidth of 81.1%. Under the load condition of 0.9 k omega, the relative bandwidth with the efficiency of more than 60% is kept at 81.1%, and the bandwidth with the efficiency of more than 50% is expanded to 100%.

Description

Technical Field

[0001] This invention belongs to the field of radio frequency environment energy harvesting technology and is applied to wireless power supply IoT devices. Specifically, it involves two Schottky diodes: diode D1 and diode D2. In a single-branch LC circuit, capacitor C1 is connected to TL1; the other end of C1 is connected to L1. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R. In a dual-branch LC circuit, due to the different matching network connections, one characteristic is that capacitor C1 is connected in series with L1 and then in parallel with C2 and L2 connected in series; the common connection point of C1 and C2 is connected to TL1; the common connection point of L1 and L2 is connected to TL2. Another characteristic is that capacitor C1 is connected in series with L1 and then in parallel with C2 and L2 connected in series; the common connection point of C1 and C2 is connected to TL1; the anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R. Background Technology

[0002] Radio frequency rectifiers play a crucial role in the field of radio frequency environmental energy harvesting. They are important functional devices that convert radio frequency beams into electrical energy to achieve efficient energy conversion. The environmental electromagnetic energy they harvest can be applied to wireless power supply IoT devices.

[0003] Radio frequency rectifiers are crucial for the practicality of wireless energy harvesting devices and systems, especially in low-power applications such as the Internet of Things (IoT) and wireless sensor networks (WSN). Therefore, rectifiers should have wide bandwidth and be miniaturized.

[0004] Radio frequency (RF) rectification efficiency is a key indicator for evaluating the performance of RF rectifier circuits. In the fields of microwave wireless power transmission and wireless communication, RF rectifiers are required to have high rectification efficiency in specific frequency bands. This means that RF rectifiers need to possess highly efficient conversion capabilities. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings or improvement needs of the existing technology by proposing a compact, broadband, frequency-insensitive rectifier for wirelessly powered IoT devices. The rectifier circuit employs a dual-branch LC series-parallel matching network, which is found to be frequency-insensitive. Impedance matching can be achieved with only one or two transmission lines, thereby reducing circuit complexity and area. Furthermore, the introduction of high-precision capacitors and inductors as an impedance compression network improves circuit stability, and the use of Schottky diodes makes it more suitable for high-frequency environments.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices includes: four capacitors: capacitor C1, capacitor C2, capacitor C3, and capacitor C4; a resistor R; one or two transmission lines; transmission line TL1 or transmission lines TL1 and TL2; and two Schottky diodes: diode D1 and diode D2, characterized in that: The capacitor C1 is connected to TL1; the other end of C1 is connected to L1. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R. Due to the different matching network connections, the dual-branch LC circuit has two characteristics: First, capacitors C1 and L1 are connected in series and then in parallel with C2 and L2 connected in series; the common junction of C1 and C2 is connected to TL1; the common junction of L1 and L2 is connected to TL2. Second, capacitors C1 and L1 are connected in series and then in parallel with C2 and L2 connected in series; the common junction of C1 and C2 is connected to TL1; the anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R.

[0007] Furthermore, the compact broadband frequency-insensitive rectifier for wireless power supply IoT devices is characterized in that: the capacitor C1 is connected in series with L1 and then connected to a transmission line TL1 for impedance matching, thereby achieving miniaturization.

[0008] Furthermore, the compact broadband frequency-insensitive rectifier for wireless power supply IoT devices is characterized in that: capacitor C1 is connected in series with L1 and then in parallel with C2 and L2 in series, which is used to reduce the real and imaginary parts of the impedance and is insensitive to frequency.

[0009] Furthermore, the aforementioned compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices is characterized in that: the operating frequency band of the single-branch LC RF rectifier is 1.1 GHz to 2.3 GHz; the operating frequency band of the dual-branch LC RF rectifier using two transmission lines is 0.7 GHz to 3 GHz; and the operating frequency band of the dual-branch LC RF rectifier using one transmission line is 1.1 GHz to 2.6 GHz.

[0010] Furthermore, the aforementioned compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices is characterized by: a single-branch LC RF rectifier achieving an RF rectification efficiency of over 40% within a bandwidth of 1.1 GHz to 2.4 GHz when the input power is 0 dBm; a dual-branch LC RF rectifier connecting two transmission lines achieving an RF rectification efficiency of over 30% within a bandwidth of 0.7 GHz to 2.6 GHz when the input power is 0 dBm; and a dual-branch LC RF rectifier connecting one transmission line achieving an RF rectification efficiency of over 40% within a bandwidth of 1.1 GHz to 2.6 GHz when the input power is 0 dBm.

[0011] Furthermore, the aforementioned compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices is characterized by: a single-branch LC RF rectifier achieving an RF rectification efficiency of over 50% within a bandwidth of 1.1 GHz to 2.4 GHz at an input power of 5 dBm; a dual-branch LC RF rectifier connecting two transmission lines achieving an RF rectification efficiency of over 40% within a bandwidth of 0.7 GHz to 2.3 GHz at an input power of 5 dBm; and a dual-branch LC RF rectifier connecting one transmission line achieving an RF rectification efficiency of over 50% within a bandwidth of 1.1 GHz to 2.6 GHz at an input power of 5 dBm.

[0012] Furthermore, the aforementioned compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices is characterized in that: a single-branch LC RF rectifier achieves an RF rectification efficiency of over 60% within a bandwidth of 1.1 GHz to 2.3 GHz when the input power is 8 dBm. A dual-branch LC RF rectifier connecting two transmission lines achieves an RF rectification efficiency of over 40% within a bandwidth of 0.7 GHz to 3 GHz and over 50% within a bandwidth of 0.8 GHz to 1.9 GHz when the input power is 8 dBm. A dual-branch LC RF rectifier connecting one transmission line achieves an RF rectification efficiency of over 60% within a bandwidth of 1.1 GHz to 2.6 GHz when the input power is 8 dBm.

[0013] Furthermore, the compact broadband frequency-insensitive rectifier for wireless power supply IoT devices, by comparison, has the following optimal circuit characteristics: when the RF rectifier input power is 8 dBm and the load is 1.2 kΩ, the RF rectification efficiency is up to 74.75% at a frequency of 1.8 GHz.

[0014] The beneficial effects of the above-described solution in this invention are as follows: This invention effectively increases the operating bandwidth of the RF rectifier by employing a dual-branch LC series-parallel impedance matching network that is insensitive to frequency changes, achieving a miniaturized design. Simultaneously, it utilizes a voltage doubler rectifier circuit structure to improve the output voltage. Furthermore, it boasts advantages such as simple construction, small size, low cost, wide bandwidth, and high efficiency. Attached Figure Description

[0015] Figure 1 This is a structural diagram of the single-branch LC radio frequency circuit of the present invention.

[0016] Figure 2 This is a schematic diagram of the radio frequency circuit structure of the present invention, which connects two transmission lines via a dual-branch LC circuit.

[0017] Figure 3 This is a schematic diagram of the radio frequency circuit structure of the present invention, which connects a dual-branch LC circuit to a single transmission line.

[0018] Figure 4 These are conversion efficiency diagrams of the single-branch LC RF rectifier in this embodiment of the invention when the input power is 0 dBm.

[0019] Figure 5 These are conversion efficiency diagrams of the single-branch LC RF rectifier in this embodiment of the invention at an input power of 5 dBm.

[0020] Figure 6 These are conversion efficiency diagrams of the single-branch LC RF rectifier in this embodiment of the invention at an input power of 8 dBm.

[0021] Figure 7 This is a conversion efficiency diagram of the RF rectifier with dual-branch LC connection of two transmission lines in an embodiment of the present invention when the input power is 0 dBm.

[0022] Figure 8 This is a conversion efficiency diagram of the RF rectifier with dual-branch LC connection of two transmission lines in an embodiment of the present invention, when the input power is 5 dBm.

[0023] Figure 9 This is a conversion efficiency diagram of the RF rectifier with dual-branch LC connection of two transmission lines in an embodiment of the present invention, when the input power is 8 dBm.

[0024] Figure 10 This is a conversion efficiency diagram of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 1.2 kΩ and an input power of 0 dBm.

[0025] Figure 11This is a diagram showing the conversion efficiency of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 1.2 kΩ and an input power of 5 dBm.

[0026] Figure 12 This is a conversion efficiency diagram of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 1.2 kΩ and an input power of 8 dBm.

[0027] Figure 13 This is a diagram showing the conversion efficiency of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 0.9 kΩ and an input power of 0 dBm.

[0028] Figure 14 This is a diagram showing the conversion efficiency of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 0.9 kΩ and an input power of 5 dBm.

[0029] Figure 15 This is a diagram showing the conversion efficiency of a dual-branch LC-connected radio frequency rectifier with a single transmission line in an embodiment of the present invention, with a load of 0.9 kΩ and an input power of 8 dBm. Detailed Implementation

[0030] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments.

[0031] like Figure 1 As shown in the embodiment of the present invention, a compact broadband frequency-insensitive rectifier for a wireless power supply IoT device is provided. Figure 1 It includes: three capacitors: C1, C3, and C4; one inductor L1; one resistor R; a transmission line TL1 with a length of 24.7 mm and a width of 0.8 mm; and two Schottky diodes: diode D1 and diode D2, characterized in that: The capacitor C1 is connected to TL1; the other end of C1 is connected to L1. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R.

[0032] like Figure 2 As shown in the embodiment of the present invention, a compact broadband frequency-insensitive rectifier for a wireless power supply IoT device is provided. Figure 2 It includes: four capacitors: C1, C2, C3, and C4; two inductors L1 and L2; one resistor R; transmission lines (TL1 and TL2) with a length of 5 mm and a width of 0.7 mm and a length of 14.9 mm and a width of 0.2 mm; and two Schottky diodes: diode D1 and diode D2; characterized in that: The capacitors C1 and L1 are connected in series and then in parallel, while C2 and L2 are connected in series. The common connection point of C1 and C2 is connected to TL1. The common connection point of L1 and L2 is connected to TL2. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R.

[0033] Figure 3 As shown in the embodiment of the present invention, a compact broadband frequency-insensitive rectifier for a wireless power supply IoT device is provided. Figure 3 Includes: four capacitors: C1, C2, C3, and C4; two inductors L1 and L2; one resistor R; a transmission line TL1 with a length of 23.2 mm and a width of 0.8 mm; and two Schottky diodes: diode D1 and diode D2. Its characteristic is that: The capacitors C1 and L1 are connected in series and then in parallel, while C2 and L2 are connected in series. The common junction of C1 and C2 is connected to TL1. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R.

[0034] To ensure the accuracy and convenience of the implementation of the scheme, the single-branch LC impedance matching network is further constructed. The network structure consists of lumped parameter elements connected to the transmission line TL1. The final determined parameters of the single-branch LC impedance matching network elements are shown in Table 1.

[0035] Table 1 Parameters of a Single-Branch LC Impedance Matching Network parameter width length TL1 0.8 mm 24.7 mm To ensure the accuracy and convenience of the implementation of the scheme, the impedance matching network for the dual-branch LC connection of the two transmission lines is further constructed. This network structure consists of lumped parameter elements connected to transmission lines TL1 and TL2. The final determined impedance matching network element parameters for the dual-branch LC connection of the two transmission lines are shown in Table 2.

[0036] Table 2 Impedance matching network parameters for dual-branch LC circuits using two transmission lines parameter width length TL1 0.7 mm 2 mm TL2 0.2 mm 14.9 mm To ensure the accuracy and convenience of the implementation of the scheme, the impedance matching network of the dual-branch LC connection to a transmission line is further constructed. This network structure consists of lumped parameter elements connected to the transmission line TL1. The final determined impedance matching network element parameters of the dual-branch LC connection to a transmission line are shown in Table 3.

[0037] Table 3 Impedance matching network parameters for dual-branch LC circuits using a single transmission line parameter width length TL1 0.8 mm 23.2 mm Furthermore, the aforementioned compact broadband frequency-insensitive rectifier for wireless power supply IoT devices is characterized in that: the single-branch LC rectifier has a capacitor C1 value of 2.4 pF, an inductor L1 value of 10 nH, a length of 19 mm, a width of 13 mm, and a substrate dielectric constant of 2.65 with a thickness of 0.8 mm; the dual-branch LC rectifier using two transmission lines has a capacitor C1 value of 8 pF, an inductor C2 value of 9.1 pF, an inductor L1 value of 24 nH, an inductor L2 value of 4.9 nH, a length of 39 mm, and a width of 8 mm; the dual-branch LC rectifier using one transmission line has a capacitor C1 value of 2.4 pF, an inductor C2 value of 1.2 pF, an inductor L1 value of 10 nH, an inductor L2 value of 22 nH, a length of 16 mm, a width of 13 mm, and a substrate dielectric constant of 2.65 with a thickness of 0.8 mm. Furthermore, the compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices consists of a voltage doubler rectifier followed by a DC filter structure, and then connected to the load resistor R. The final component parameters of the DC filter are shown in Table 4.

[0038] Table 4 Component parameters of DC filters parameter numerical values parameter numerical values C3 100 pF C4 100 pF Furthermore, Figure 4 The efficiency of a single-branch LC RF rectifier is given. When the input power is 0 dBm, the RF rectification efficiency of the single-branch LC RF rectifier is above 40% in the bandwidth of 1.1 GHz to 2.4 GHz.

[0039] Furthermore, Figure 5 The efficiency of a single-branch LC RF rectifier is given. When the input power is 5 dBm, the RF rectification efficiency of the single-branch LC RF rectifier is above 50% in the bandwidth of 1.1 GHz to 2.4 GHz.

[0040] Furthermore, Figure 6 The efficiency of a single-branch LC RF rectifier is given. When the input power is 8 dBm, the RF rectification efficiency of the single-branch LC RF rectifier is above 60% in the bandwidth of 1.1 GHz to 2.3 GHz.

[0041] Furthermore, Figure 7 The efficiency of a dual-branch LC-connected RF rectifier with two transmission lines is presented. When the input power is 0 dBm, the RF rectification efficiency of the dual-branch LC-connected RF rectifier with two transmission lines is above 30% in the bandwidth of 0.7 GHz to 2.6 GHz.

[0042] Furthermore, Figure 8The efficiency of a dual-branch LC-connected RF rectifier with two transmission lines is presented. The RF rectifier with two branch LC-connected transmission lines has an RF rectification efficiency of over 40% in the bandwidth of 0.7 GHz to 2.3 GHz when the input power is 5 dBm.

[0043] Furthermore, Figure 9 The efficiency of a dual-branch LC-connected RF rectifier with two transmission lines is presented. When the input power is 8 dBm, the RF rectifier with two transmission lines has an RF rectification efficiency of over 40% in the bandwidth of 0.7 GHz to 3 GHz and an RF rectification efficiency of over 50% in the bandwidth of 0.8 GHz to 1.9 GHz.

[0044] Furthermore, Figure 10 The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line is presented. When the input power is 0 dBm and the load is 1.2 kΩ, the RF rectification efficiency of the dual-branch LC-connected RF rectifier with a single transmission line is above 40% within a bandwidth of 1.1 GHz to 2.6 GHz.

[0045] Furthermore, Figure 11 The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line is presented. The RF rectifier with a dual-branch LC-connected RF rectifier with a single transmission line has an RF rectification efficiency of over 50% in the bandwidth of 1.1 GHz to 2.6 GHz when the input power is 5 dBm and the load is 1.2 kΩ.

[0046] Furthermore, Figure 12 The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line is presented. With an input power of 8 dBm and a load of 1.2 kΩ, the RF rectification efficiency of the dual-branch LC-connected RF rectifier with a single transmission line is above 60% within a bandwidth of 1.1 GHz to 2.6 GHz.

[0047] Furthermore, Figure 13 The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line at 0 dBm is given.

[0048] Furthermore, Figure 14 The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line at 5 dBm is given.

[0049] Furthermore, Figure 15The efficiency of a dual-branch LC-connected RF rectifier with a single transmission line at 8 dBm is presented. By comparing the efficiency at three different power levels, the optimal RF rectifier input power is 8 dBm. When the optimal load is 0.9 kΩ and the frequency is 1.8 GHz, the RF rectification efficiency is the highest at 72.67%. The RF rectification efficiency is above 60% within the bandwidth of 1.1 GHz to 2.6 GHz and above 50% within the bandwidth of 0.9 GHz to 2.7 GHz.

[0050] Brief working principle of the invention: To achieve a small size and wide bandwidth performance for the RF rectifier, an RF rectifier based on a dual-branch LC series-parallel impedance matching network that is insensitive to frequency changes is adopted, which effectively improves the operating bandwidth and conversion efficiency of the RF rectifier. Subsequently, a voltage doubler rectification structure is used to improve the output DC voltage.

Claims

1. A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices, the single-branch LC rectifier comprising: A rectifier using two transmission lines in a dual-branch LC circuit includes: three capacitors: C1, C3, and C4; one inductor L1; one resistor R; a transmission line TL1 with a length of 24.7 mm and a width of 0.8 mm; two Schottky diodes: diode D1 and diode D2; and a rectifier using one transmission line in a dual-branch LC circuit includes: four capacitors: C1, C2, C3, and C4; two inductors L1 and L2; one resistor R; transmission lines TL1 and TL2 with a length of 5 mm and a width of 0.7 mm and 14.9 mm and a width of 0.2 mm, respectively; and two Schottky diodes: diode D1 and diode D2. A rectifier using one transmission line in a dual-branch LC circuit includes: four capacitors: C1, C2, C3, and C4; two inductors L1 and L2; one resistor R; and a transmission line TL1 with a length of 23.2 mm and a width of 0.8 mm. The transmission line TL1 is mm; two Schottky diodes: diode D1 and diode D2, characterized in that: in a single-branch LC rectifier, capacitor C1 is connected to TL1; the other end of C1 is connected to L1. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R. In a dual-branch LC rectifier, due to the different matching network connections, one characteristic is that: capacitor C1 is connected in series with L1 and then in parallel with C2 and L2 connected in series; the common junction of C1 and C2 is connected to TL1; the common junction of L1 and L2 is connected to TL2; another characteristic is that: capacitor C1 is connected in series with L1 and then in parallel with C2 and L2 connected in series; the common junction of C1 and C2 is connected to TL1; the anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitors C3 and C4 and resistor R.

2. A compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices according to claim 1, characterized in that: The capacitor C1 is connected in series with L1 and then connected to a transmission line TL1 for impedance matching, thereby achieving miniaturization.

3. A compact broadband frequency-insensitive rectifier for wireless power supply IoT devices according to claim 1, characterized in that: The capacitors C1 and L1 are connected in series, and then C2 and L2 are connected in parallel in series. This is used to reduce the real and imaginary parts of the impedance and is not sensitive to frequency.

4. A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices according to claim 1, characterized in that: The operating frequency band of a single-branch RF rectifier is 1.1 GHz to 2.3 GHz; the operating frequency band of a dual-branch RF rectifier using two transmission lines is 0.7 GHz to 3 GHz; and the operating frequency band of a dual-branch RF rectifier using one transmission line is 1.1 GHz to 2.6 GHz.

5. A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices according to claim 1, characterized in that: A single-branch LC RF rectifier achieves an RF rectification efficiency of over 40% within a bandwidth of 1.1 GHz to 2.4 GHz at an input power of 0 dBm. A dual-branch LC RF rectifier connecting two transmission lines achieves an RF rectification efficiency of over 30% within a bandwidth of 0.7 GHz to 2.6 GHz at an input power of 0 dBm. A dual-branch LC RF rectifier connecting one transmission line achieves an RF rectification efficiency of over 40% within a bandwidth of 1.1 GHz to 2.6 GHz at an input power of 0 dBm.

6. A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices according to claim 1, characterized in that: A single-branch LC RF rectifier achieves an RF rectification efficiency of over 50% within a bandwidth of 1.1 GHz to 2.4 GHz at an input power of 5 dBm. A dual-branch LC RF rectifier connecting two transmission lines achieves an RF rectification efficiency of over 40% within a bandwidth of 0.7 GHz to 2.3 GHz at an input power of 5 dBm. A dual-branch LC RF rectifier connecting one transmission line achieves an RF rectification efficiency of over 50% within a bandwidth of 1.1 GHz to 2.6 GHz at an input power of 5 dBm.

7. A compact broadband frequency-insensitive rectifier for wirelessly powered Internet of Things (IoT) devices according to claim 1, characterized in that: A single-branch LC RF rectifier achieves an RF rectification efficiency of over 60% within a bandwidth of 1.1 GHz to 2.3 GHz at an input power of 8 dBm. A dual-branch LC RF rectifier connecting two transmission lines achieves an RF rectification efficiency of over 40% within a bandwidth of 0.7 GHz to 3 GHz and over 50% within a bandwidth of 0.8 GHz to 1.9 GHz at an input power of 8 dBm. A dual-branch LC RF rectifier connecting one transmission line achieves an RF rectification efficiency of over 60% within a bandwidth of 1.1 GHz to 2.6 GHz at an input power of 8 dBm.

8. A compact broadband frequency-insensitive rectifier for wirelessly powered IoT devices according to claim 1, wherein, by comparison, the optimal circuit is characterized by: With an input power of 8 dBm and a load of 1.2 kΩ, the maximum RF rectification efficiency is 74.75% at a frequency of 1.8 GHz; with a load of 0.9 kΩ, the maximum RF rectification efficiency is 72.67% at a frequency of 1.8 GHz. The RF rectification efficiency is above 60% within a bandwidth of 1.1 GHz to 2.6 GHz, and above 50% within a bandwidth of 0.9 GHz to 2.7 GHz.

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