Wireless wire - ultra-low-power and high-data-rate wireless communication systems

With the rapid development of communication technologies, wireless personal-area communication systems gain momentum and become increasingly important. When the market gets gradually saturated and the technology becomes much more mature, new demands on higher throughput push the wireless communication further into the high-frequency and high-data-rate direction. For example, in the IEEE 802.15.3c standard, a 60-GHz physical layer is specified, which occupies the unlicensed 57 to 64 GHz band and supports gigabit links for applications such as wireless downloading and data streaming. Along with the progress, however, both wireless protocols and physical systems and devices start to become very complex. Due to the limited cut-off frequency of the technology and high parasitic and noise levels at high frequency bands, the power consumption of these systems, especially of the RF front-ends, increases significantly. The reason behind this is that RF performance does not scale with technology at the same rate as digital baseband circuits. Based on the challenges encountered, the wireless-wire system is proposed for the millimeter wave high-data-rate communication. In this system, beamsteering directional communication front-ends are used, which confine the RF power within a narrow beam and increase the level of the equivalent isotropic radiation power by a factor equal to the number of antenna elements. Since extra gain is obtained from the antenna beamsteering, less front-end gain is required, which will reduce the power consumption accordingly. Besides, the narrow beam also reduces the interference level to other nodes. In order to minimize the system average power consumption, an ultra-low power asynchronous duty-cycled wake-up receiver is added to listen to the channel and control the communication modes. The main receiver is switched on by the wake-up receiver only when the communication is identified while in other cases it will always be in sleep mode with virtually no power consumed. Before transmitting the payload, the event-triggered transmitter will send a wake-up beacon to the wake-up receiver. As long as the wake-up beacon is longer than one cycle of the wake-up receiver, it can be captured and identified. Furthermore, by adopting a frequency-sweeping injection locking oscillator, the wake-up receiver is able to achieve good sensitivity, low latency and wide bandwidth simultaneously. In this way, high-data-rate communication can be achieved with ultra-low average power consumption. System power optimization is achieved by optimizing the antenna number, data rate, modulation scheme, transceiver architecture, and transceiver circuitries with regards to particular application scenarios. Cross-layer power optimization is performed as well. In order to verify the most critical elements of this new approach, a W-band injection-locked oscillator and the wake-up receiver have been designed and implemented in standard TSMC 65-nm CMOS technology. It can be seen from the measurement results that the wake-up receiver is able to achieve about -60 dBm sensitivity, 10 mW peak power consumption and 8.5 µs worst-case latency simultaneously. When applying a duty-cycling scheme, the average power of the wake-up receiver becomes lower than 10 µW if the event frequency is 1000 times/day, which matches battery-based or energy harvesting-based wireless applications. A 4-path phased-array main receiver is simulated working with 1 Gbps data rate and on-off-keying modulation. The average power consumption is 10 µW with 10 Gb communication data per day

Application of systems engineering to complex systems and system of systems

2017 Spring.Includes bibliographical references.This dissertation is an investigation of system of systems (SoS). It begins with an analysis to define, with some rigor, the similarities and differences between complex systems and SoS. With this foundation, the baseline concept is development for several different types of systems and they are used as a practical approach to compare and contrast complex systems versus SoS. The method is to use a progression from simple to more complex systems. Specifically, a pico hydro electric power generation system, a hybrid renewable electric power generation system, a LEO satellites system, and Molniya orbit satellite system are investigated. In each of these examples, systems engineering methods are applied for the development of a baseline solution. While these examples are complex, they do not rise to the level of a SoS. In contrast, a multi-spectral drone detection system for protection of airports is investigated and a baseline concept for it is generated. The baseline is shown to meet the minimum requirements to be considered a SoS. The system combines multiple sensor types to distinguish drones as targets. The characteristics of the drone detection system which make it a SoS are discussed. Since emergence is considered by some to be a characteristic of a SoS, it is investigated. A solution to the problem of determining if system properties are emergent is presented and necessary and sufficient conditions for emergence are developed. Finally, this work concludes with a summary and suggestions for additional work

Compact and Efficient Millimetre-Wave Circuits for Wideband Applications

Radio systems, along with the ever increasing processing power provided by computer technology, have altered many aspects of our society over the last century. Various gadgets and integrated electronics are found everywhere nowadays; many of these were science-fiction only a few decades ago. Most apparent is perhaps your ``smart phone'', possibly kept within arm's reach wherever you go, that provides various services, news updates, and social networking via wireless communications systems. The frameworks of the fifth generation wireless system is currently being developed worldwide. Inclusion of millimetre-wave technology promise high-speed piconets, wireless back-haul on pencil-beam links, and further functionality such as high-resolution radar imaging. This thesis addresses the challenge to provide signals at carrier frequencies in the millimetre-wave spectrum, and compact integrated transmitter front-ends of sub-wavelength dimensions. A radio frequency pulse generator, i.e. a ``wavelet genarator'', circuit is implemented using diodes and transistors in III--V compound semiconductor technology. This simple but energy-efficient front-end circuit can be controlled on the time-scale of picoseconds. Transmission of wireless data is thereby achieved at high symbol-rates and low power consumption per bit. A compact antenna is integrated with the transmitter circuit, without any intermediate transmission line. The result is a physically small, single-chip, transmitter front-end that can output high equivalent isotropically radiated power. This element radiation characteristic is wide-beam and suitable for array implementations

Module, Filter, And Antenna Technology For Millimeter Waves Multi-gigabits Wireless Systems

A method of fabricating an ultra-high frequency module is disclosed. The method includes providing a top layer; drilling the top layer; milling the top layer; providing a bottom; milling the bottom layer to define a bottom layer cavity; aligning the top layer and the bottom layer; and adhering the top layer to the bottom layer. The present invention also includes an ultra-high frequency module operating at ultra-high speeds having a top layer, the top layer defining a top layer cavity; a bottom layer, the bottom layer defining a bottom layer cavity; and an adhesive adhering both the top layer to the bottom layer, wherein the top layer and the bottom layer are formed from a large area panel of a printed circuit board.Georgia Tech Research Corporatio

Hybrid Integrated Ultra-Broadband Optical Receiver for Radio-over-Fiber Application

Communication is an integral part of people’s daily life, and its demand will never cease. After multiple generations of communication system improvement, broadband wireless communication has become a conspicuous development trend but the congested spectrum has turned into one of the system bottlenecks. Therefore, shifting into higher frequency bands, that is, wavelengths of millimeter scale would be a solution to suffice the escalating consumer demand, and Radio-over-Fiber (RoF) is the key for successful system deployment. Under RoF structure, Radio Frequency (RF) signals can be directly distributed from central station to base stations via optical fiber, as a result, size of base station can be implemented into a palm-size package, and more importantly, lower unit cost of base stations crucial due to high volume use. In this work, we started with the design of an optical receiver as the first step of transceiver integration, and targeted at 40 GHz or above. Different from the widespread digital optical receiver, optical nature of RoF transmission is analog signal, and consequently its receiver demands higher qualification standards. Noise, intermodulation distortion, nonlinearities and other aspects are all required to be validated. Putting the cost factor into consideration, we used Miniature Hybrid Microwave Integrated Circuit (MHMIC) technology to implement our analog optical receiver. Design and simulation of the 40 GHz receiver was mainly carried out by Agilent Advanced Design System (ADS), and the bondwire interconnection is identified as a major potential bandwidth degradation factor of the receiver. After the circuit fabrication, the S-parameter results showed the receiver bandwidth is limited to 30 GHz due to certain fabrication error caused by bondwires. The bandwidth evaluation is further verified from Error Vector Magnitude (EVM) results by transmitting Ultra-wideband (UWB) signal centered at 30.31 GHz through a 20 KM long optical fiber. In back-to-back characterization of the receiver, the 1-dB compression point is found as 11.7 dBm (referred to input) and the SFDR based on two sets of two-tone frequencies (4 GHz with 6 GHz, and 13 GHz with 14 GHz) is 107.45 dB/Hz2/3. Responsivity of the receiver is 0.325 A/W at 1550 nm