RF powering of millimeter- and submillimeter-sized neuralprosthetic implants

The size of the transducers for neural stimulation has shrunk steadily with application of thin-film techniques to electrode design. The feasibility is examined of designing millimeter- and submillimeter-sized power sources based on RF coupling that could be integrated into these implants to provide power without a tethering power cable. The coupling between a transmitter coil and receiver coil when the coil diameters are markedly different is analyzed, and for these circumstances, a simple Thevenin equivalent model is developed to describe the power transmission between the transmitter and receiver. The equivalent circuit developed gives insight into the way that coil diameters, frequency, and turns affect coupling between large and small coils. Several examples demonstrate that milliwatt range power sources can be implemented with millimeter- and submillimeter-diameter receivers     

带负载匹配耦合谐振电路的能量与数据传输

为了提高耦合谐振电路中负载端的工作距离,使其达到30 cm 以上,并且能从负载端传输数据回发射端,基于频率分裂原理,设计了带负载匹配的能量与数据传输电路.对串联电路研究可知,满足一定传输功率的最大传输距离和负载阻值相关.而带负载匹配的串并混联电路在小幅降低传输功率的情况下可以通过调整等效负载电阻大小来增加传输距离.基于反向散射原理和混联电路的负载特性,可以在均衡传输效率和传输距离的情况下,选取合理的负载调制电路,实现数据从负载端到发射端的传输.matlab 仿真验证了以上结论,而系统实测表明,相比于串联电路,串并混联在保证数据正确传输的前提下,极限工作距离达到38 cm,提升20%以上.     

一种Ku波段行波管发射机的设计

介绍一种Ku波段行波管发射机的技术参数及其设计方法.主要叙述了系统的构成:高压电源、监控电路和调制器的设计,并针对发射机在无人机载SAR方面的应用,就如何解决体积小、重量轻情况下的电磁兼容问题,低气压条件下的高压绝缘与散热矛盾作了较详细说明.     

Implantable 9-channel telemetry system for in vivo load measurements with orthopedic implants.

Knowledge of the loads to which orthopedic implants are subjected is a fundamental prerequisite for their optimal biomechanical design, long-term success, and improved rehabilitation outcomes. In vivo load measurements are more accurate than those obtained using mathematical musculoskeletal models. An inductively powered integrated circuit inside the implant measures six load components as well as the temperature and supplied voltage. This low-power circuit includes a 9-channel multiplexer, a programmable memory, a pulse interval modulator, and a radio-frequency transmitter. Together with a few passive components, the integrated circuit is mounted on a ceramic substrate with thick-film hybrid technology. The sensor signals are multiplexed, modulated, and transmitted to an external device. The microcontroller of the external device regulates the alternating magnetic field produced by a power oscillator and synchronizes the pulse interval modulated data stream. A personal computer displays forces, moments, and temperatures in real time. The new telemetry transmitter has, thus far, been used for in vivo load measurements in three patients with shoulder endoprostheses. Eight instrumented vertebral body replacements are ready for implantation, and an instrumented tibial tray is being submitted to laboratory tests.     

Implantable 9-Channel Telemetry System for In Vivo Load Measurements With Orthopedic Implants

Knowledge of the loads to which orthopedic implants are subjected is a fundamental prerequisite for their optimal biomechanical design, long-term success, and improved rehabilitation outcomes. In vivo load measurements are more accurate than those obtained using mathematical musculoskeletal models. An inductively powered integrated circuit inside the implant measures six load components as well as the temperature and supplied voltage. This low-power circuit includes a 9-channel multiplexer, a programmable memory, a pulse interval modulator, and a radio-frequency transmitter. Together with a few passive components, the integrated circuit is mounted on a ceramic substrate with thick-film hybrid technology. The sensor signals are multiplexed, modulated, and transmitted to an external device. The microcontroller of the external device regulates the alternating magnetic field produced by a power oscillator and synchronizes the pulse interval modulated data stream. A personal computer displays forces, moments, and temperatures in real time. The new telemetry transmitter has, thus far, been used for in vivo load measurements in three patients with shoulder endoprostheses. Eight instrumented vertebral body replacements are ready for implantation, and an instrumented tibial tray is being submitted to laboratory tests     

Transcutaneous RF-powered implantable minipump driven by a class-E transmitter

We describe the design and testing of an inductive coupling system used to power an implantable minipump for applications in ambulating rats. A 2 MHz class-E oscillator driver powered a coil transmitter wound around a 33-cm-diameter rat cage. A receiver coil, a filtered rectifier, and a voltage-sensitive switch powered the implant. The implant DC current at the center of the primary coil (5.1 V) exceeded the level required to activate the solenoid valve in the pump. The variations of the implant current in the volume of the primary coil reflected the variations of the estimated coupling coefficient between the two coils. The pump could be activated in-vivo, while accommodating the vertical and horizontal movements of the animal. Advantages of this design include a weight reduction for the implant, an operation independent from a finite power source, and a remote activation/deactivation.     

Receiver Power Allocation and Transmitter Power Control Analysis for Multiple-Receiver Wireless Power Transfer Systems

As different power has its own receivers, this paper analyzes and designs a multiple-receiver wireless power transfer (WPT) system systematically. The equivalent circuit model of the system is established to analyze the key parameters including transmitter power, receiver power, transmission efficiency, and each receiver power allocation. A control circuit is proposed to achieve the maximum transmission efficiency and transmitter power control and arbitrary receiver power allocation ratios for different receivers. Through the proposed control circuit, receivers with different loads can allocate appropriate power according to its power demand, the transmitter power and system efficiency do not vary with the change of the number of receivers. Finally, this control circuit is validated using a 130-kHz WPT system with three receivers whose power received is 3:10:12, and the overall system efficiency can reach as high as 55.5%.     

An innovative power regulation method applied for wireless magnetic-energy transportation

An innovative power regulation design and realization is proposed for wireless micro-power transmission. The proposed power regulation method is employed to regulate the power intensity transmitted by magnetic flux transmitter, based on distance change and angle misalignment between transmitter and receiver. Therefore, not only the power transmitted by magnetic flux transmitter is adjustable, but also consistent power received by locomotive devices can be achieved. Firstly, by Faraday’s law and Kirchhoff’s circuit law, the dynamic equation for proposed wireless power transmission is constructed. The distance change and angle misalignment between transmitter and receiver are also considered to reflect the influence on power received by micro-devices. In order to ensure that the power received by receiver is consistent at various locations along an ellipse trajectory, the sliding mode controller is synthesized to regulate the power transmitted by the magnetic energy source. In addition, the sliding mode estimator is also employed so that not only the system states can be estimated, but also the cost for sensors and the physical size of secondary side can be much reduced. By intensive simulation, no matter which distance and misalignment angle between transmitter and receiver is present, stable and consistent power at receiver can be achieved. Finally, the test rig for wireless micro-power transmission is constructed for performance verification. The experimental result shows that the constant power at receiver can be obtained if the SMC controller is applied to regulate the output power by transmitter.     

An implantable wireless powered light source

A wireless powered small volume light source composed of light emitting diode(LED) array is developed for implantation. According to the volt-ampere characteristics of LED and the load characteristics of coil coupling power supply, the light power and work distance of implant LED-array are optimized by changing the number and series-parallel connection mode of LEDs in receiver. The wireless powered implant can provide 5.4 m W light. The entire implant is seamlessly packaged within parylene, a biocompatible material, coating by chemical vapor depositing. The volume of the implant is 9 mm×4 mm×3 mm, the weight of which is only 0.25 g. The device can work continuously for more than three weeks in 0.9% saline and the prime prototype of the device has been validated by animal implantation.     

A low-power 2.4-GHz transmitter/receiver CMOS IC

A 2.4-GHz CMOS receiver/transmitter incorporates circuit stacking and noninvasive baseband filtering to achieve a high sensitivity with low power dissipation. Using a single 1.6-GHz local oscillator, the transceiver employs two upconversion and downconversion stages while providing on-chip image rejection filtering. Realized in a 0.25-/spl mu/m digital CMOS technology, the receiver exhibits a noise figure of 6 dB and consumes 17.5 mW from a 2.5-V supply, and the transmitter delivers an output power of 0 dBm with a power consumption of 16 mW.     

A high efficiency transmitter and receiver for magnetic resonant wireless battery charging system in 0.35 μm BCD

This paper presents a transmitter and receiver for magnetic resonant wireless battery charging system. In the receiver, a wide-input range CMOS multi-mode active rectifier is proposed for a magnetic resonant wireless battery charging system. The configuration is automatically changed with respect to the magnitude of the input AC voltage. The output voltage of the multi-mode rectifier is sensed by a comparator. Furthermore, the configuration of the multi-mode rectifier is automatically selected by switches as original rectifier mode, 1-stage voltage multiplier or 2-stage voltage multiplier mode. As a result, a rectified DC voltage is output from 7.5 to 19 V for an input AC voltage of 5–20 V. In the transmitter, a class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. This chip is implemented using 0.35 μm BCD technology with an active area of around 5,000 × 2,500 μm. When the magnitude of the input AC voltage is 10 V, the power conversion efficiency of the multi-mode active rectifier is about 94 %.The maximum power efficiency of the receiver is about 70 %. The transmitter provides an output power control range of 10–30.2 dBm. The maximum power efficiency of the PA is 71.5 %.     

反向散射通信辅助的认知无线能量通信网络的时间分配研究

为了改善次发射机的性能,本文在衬底式(Underlay)认知无线能量通信网络(Cognitive Wireless Powered Communication Networks, CWPCNs)中提出了一种新的网络模型,该网络含有一个主发射机和两个由次发射机和次接收机组成的次用户对。次发射机可工作在反向散射通信(Backscatter Communication, BackCom)和收集再传输(Harvest-then-transmit, HTT)两种协议下。针对提高次网络的系统容量,根据收集的能量是否可以驱动次发射机工作,本文考虑了三种场景并针对每种场景设计了最优的时间分配方案。仿真结果表明,相比于单独利用BackCom或HTT协议以及协作式CWPCN,本文提出的新方法性能更佳。      

Multigigabit multichannel optical interconnection module forbroadband switching system

This paper describes optical transmitter and receiver modules for package-to-package interconnection in broadband switching networks such as an asynchronous transfer mode switch fabric. These modules, which include the multiplexer and demultiplexer, can reduce the number of connections and the problem of skew between links. Five-channel optical transmitter and receiver modules were fabricated and demonstrated at 2.8 Gbit/s with a power dissipation of 4.5 W per channel. Moreover, temperature-insensitive optical interconnection was successfully demonstrated by driving a laser with a constant bias current over the threshold and by deducting the optical signal offset. The output power of the transmitter module was -4.2 dBm. Nonuniformity of the transmitter output powers across the range of optical channels was <2.1 dB. Receiver sensitivity for a bit error rate of 10^-11 was -9.3 dBm. Nonuniformity of the receiver sensitivities was <1.5 dB. The power penalty of the receiver sensitivity due to crosstalk was 1 dB. The connection distance was >250 m     

某车载固态发射机的冷却系统设计

对某车载固态发射机内部功放组件和其他集中热源的散热问题进行了研究,完成了整个机柜系统冷却系统设计。计算证明在车载方舱的工作环境下,采用强迫空气冷却能满足车载固态发射机的散热要求。     

Analysis and design of inductive coupling and transceiver circuit for inductive inter-chip wireless superconnect

A wireless bus for stacked chips was developed by utilizing inductive coupling among them. This paper discusses inductor layout optimization and transceiver circuit design. The inductive coupling is analyzed by a simple equivalent circuit model, parameters of which are extracted by a magnetic field model based on the Biot-Savart law. Given communication distance, transmit power, data rate, and SNR budget, inductor layout size is minimized. Two receiver circuits, signal sensitive and yet noise immune, are designed for inductive nonreturn-to-zero (NRZ) signaling where no signal is transmitted when data remains the same. A test chip was fabricated in 0.35-/spl mu/m CMOS technology. Accuracy of the models is verified. Bit-error rate is investigated for various inductor layouts and communication distance. The maximum data rate is 1.25 Gb/s/channel. Power dissipation is 43 mW in the transmitter and 2.6 mW in the receiver at 3.3 V. If chip thickness is reduced to 30 /spl mu/m in 90-nm device generation, power dissipation will be 1 mW/channel or bandwidth will be 1 Tb/s/mm/sup 2/.     

Power minimization and technology comparisons for digitalfree-space optoelectronic interconnections

This paper investigates the design optimization of digital free-space optoelectronic interconnections with a specific goal of minimizing the power dissipation of the overall link, and maximizing the interconnect density. To this end, we discuss a method of minimizing the total power dissipation of an interconnect link at a given bit rate. We examine the impact on the link performance of two competing transmitter technologies, vertical cavity surface emitting lasers (VCSELs) and multiple quantum-well (MQW) modulators and their associated driver-receiver circuits including complementary metal-oxide-semiconductor (CMOS) and bipolar transmitter driver circuits, and p-n junction photodetectors with multistage transimpedance receiver circuits. We use the operating bit-rate and on-chip power dissipation as the main performance measures. Presently, at high bit rates (>800 Mb/s), optimized links based on VCSELs and MQW modulators are comparable in terms of power dissipation. At low bit rates, the VCSEL threshold power dominates. In systems with high bit rates and/or high fan-out, a high slope efficiency is more important for a VCSEL than a low threshold current. The transmitter driver circuit is an important component in a link design, and it dissipates about the same amount of power as that of the transmitter itself. Scaling the CMOS technology from 0.5 μm down to 0.1 μm brings a 50% improvement in the maximum operating bit rate, which is around 4 Gb/s with 0.1 μm CMOS driver and receiver circuits. Transmitter driver circuits implemented with bipolar technology support a much higher operating bandwidth than CMOS technology; they dissipate, however, about twice the electrical power. An aggregate bandwidth in excess of 1 Tb/s-cm² can be achieved in an optimized free-space optical interconnect system using either VCSELs or MQW modulators as its transmitters     

Analysis and application of a novel model for estimating powerdissipation of optical interconnections as a function of transmissionbit error rate

This paper proposes a novel model for estimating power dissipation of optical/electrical interconnections as a function of transmission bit error rate. This model is applied to a simplified optoelectronic transmitter and receiver configuration in which a photodetector is directly connected to the decision circuit. It is analytically verified that this configuration can achieve error-free operation with low power under practical operating conditions. A comparison between optical and electrical interconnections based on this simplified configuration is performed. This result shows the interconnection length and bit rate at which optical interconnection is superior in terms of power dissipation to electrical interconnection, Only optical interconnections achieve error-free operation with 40 mW power dissipation at a transmission bit rate of 10 Gb/s and an interconnection length over 7 m     

L波段液冷固态功放组件的设计

功放组件是固态雷达发射机的重要组成部分,其热设计已成为发射机可靠性水平的重要标志之一。本文介绍了一种输出功率在工作频带内达2kW的液冷功放组件,对其电讯设计、电磁兼容及热设计都做了详细的阐述。该组件已运用于某型号雷达中。     

无源感应数据传输系统的设计与实现

针对无源感应数据传输系统工作环境中金属涡流损耗大、接收天线尺寸小等条件造成的数据传输距离短的问题,在发射机中设计了C类功率放大器,对环形发射天线进行了改进,接收机中设计了稳定的升压电路,选用了低功耗的PIC16LF877A处理器,通过这些方法增大了数据传输的距离。所设计的系统性能稳定,数据传输距离为15cm,并符合实时性和可靠性的要求。     

Low-Power Small-Area Digital I/O Cell

A novel low-power and small-area digital I/O cell is proposed in this work. The new input/output (I/O) cell drastically reduces the I/O power consumption, which has been considered as the major power dissipation of the whole chip. The maximum operating clock is 500 MHz given a 10-pF offchip load. On top of the power saving feature, the proposed cell occupies merely$10535.2=4167.45 ( transmitter)$$+6367.8 ( receiver) muhbox m^2$which is far less than any prior commercially available I/O and low-voltage differential signaling I/O cells. Physical measurements of the proposed I/O cells show that the delays of the transmitter and the receiver are 1.1 and 1.8 ns, respectively. The largest power/bandwidth of the proposed design is 38.9$mu hbox W/MHz$when transmitting.