abstract: The universe since its formation 13.7 billion years ago has undergone many changes. It began with expanding and cooling down to a temperature low enough for formation of atoms of neutral Hydrogen and Helium gas. Stronger gravitational pull in certain regions caused some regions to be denser and hotter than others. These regions kept getting denser and hotter until they had centers hot enough to burn the hydrogen and form the first stars, which ended the Dark Ages. These stars did not live long and underwent violent explosions. These explosions and the photons from the stars caused the hydrogen gas around them to ionize. This went on until all the hydrogen gas in the universe was ionized. This period is known as Epoch Of Reionization. Studying the Epoch Of Reionization will help understand the formation of these early stars, the timeline of the reionization and the formation of the stars and galaxies as we know them today. Studying the radiations from the 21cm line in neutral hydrogen, redshifted to below 200MHz can help determine details such as velocity, density and temperature of these early stars and the media around them. The EDGES program is one of the many programs that aim to study the Epoch of Reionization. It is a ground-based project deployed in Murchison Radio-Astronomy Observatory in Western Australia. At ground level the Radio Frequency Interference from the ionosphere and various man-made transmitters in the same frequency range as the EDGES receiver make measurements, receiver design and extraction of useful data from received signals difficult. Putting the receiver in space can help majorly escape the RFI. The EDGES In Space is a proposed project that aims at designing a receiver similar to the EDGES receiver but for a cubesat. This thesis aims at designing a prototype receiver that is similar in architecture to the EDGES low band receiver (50-100MHz) but is significantly smaller in size (small enough to fit on a PCB for a cubesat) while keeping in mind different considerations that affect circuit performance in space. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2019

<p>This thesis work carries out a study of IEEE 802.16 standards and mainly concentrates on the 802.16a OFDM PHY layer. A Simulink model based on 802.16a OFDM PHY baseband is built for simulation and performance evaluation. All mandatory blocks in the 802.16a OFDM-PHY specification are included: Randomization, FEC,adaptive modulation, and IFFT/FFT. A multipath Rayleigh fading channel is implemented and frequency domain channel estimation is selected for this model. Perfect synchronization is assumed.</p>

<p>Real-time systems are systems which must produce a result within a given time frame. A result given outside of this time frame is as useless as not delivering any result at all. It is therefore essential to verify that real-time systems fulfill their timing requirements. A model of the system can facilitate the verification process. This thesis investigates two possible methods for modeling a real-time system with respect to CPU-utilization and latency of the different components in the system. The two methods are evaluated and one method is chosen for implementation.The studied system is the decoder of a WCDMA system which utilizes a real-time operating called system OSEck. The methodology of analyzing the system and different ways of obtaining measurements to base the model upon will be described. The model was implemented using the simulation library VirtualTime, which contains a model of the previously mentioned operating system. Much work was spent acquiring input for the model, since the quality of the model depends largely on the quality of the analysis work. The model created contains two of the studied systems main components.This thesis identifies thorough system knowledge and efficient profiling methods as the key success factors when creating models of real-time systems.</p>

This thesis work carries out a study of IEEE 802.16 standards and mainly concentrates on the 802.16a OFDM PHY layer. A Simulink model based on 802.16a OFDM PHY baseband is built for simulation and performance evaluation. All mandatory blocks in the 802.16a OFDM-PHY specification are included: Randomization, FEC,adaptive modulation, and IFFT/FFT. A multipath Rayleigh fading channel is implemented and frequency domain channel estimation is selected for this model. Perfect synchronization is assumed.

The thesis is mainly in algorithm design and implementation of hardware circuit of baseband signal processing at the transceiver of 2450 MHz band chirp spread spectrum in IEEE 802.15.4a ¡V 2007 Low Rate-Wireless Personal Area Network (LR-WPAN). Due to the characteristic of LR-WPAN such as low cost, low power consumption, small size and easy to implementation, we have to take the complexity and the system performance into consideration. In this thesis, we study on the algorithm design of baseband signal, and analysis the simulation result. At the transmitter, following the specification and realize it. At the receiver, designing the algorithm including the packet detection, energy detection and down-sampling, carrier frequency offset estimation and compensation, timing synchronization, and bi-orthogonal demapper. The system performance after quantizing is 3dB better than the receiver sensitivity we expected. After finishing the algorithm design of the transceiver, we implement the baseband signal circuit by using Verilog Code. Finally, we make an application to National Chip Implementation Center (CIC), and will measure the circuit after the chip tape out. The circuit is fabricated in a 0.18-£gm CMOS technology.

The International Technology Roadmap for Semiconductors projects that embedded memories will occupy increasing System-on-Chip area. The growing density of integration increases the likelihood of fabrication faults. The proposed memory repair strategy employs forward error correction at the system level and mitigates the impact of memory faults through permutation of high sensitivity regions. The effectiveness of the proposed repair technique is demonstrated on a 19.4-Mbit de-interleaver SRAM memory of an ISDB-T digital baseband OFDM receiver in 65-nm CMOS. The proposed technique introduces a single multiplexer delay overhead and a configurable area overhead of M/i bits, where M is the number of memory rows and i is an integer from 1 to M, inclusive. The proposed strategy achieves a measured 0.15 dB gain improvement at a 2e-4 Quasi-Error-Free (QEF) BER in the presence of memory faults for an AWGN channel.

The International Technology Roadmap for Semiconductors projects that embedded memories will occupy increasing System-on-Chip area. The growing density of integration increases the likelihood of fabrication faults. The proposed memory repair strategy employs forward error correction at the system level and mitigates the impact of memory faults through permutation of high sensitivity regions. The effectiveness of the proposed repair technique is demonstrated on a 19.4-Mbit de-interleaver SRAM memory of an ISDB-T digital baseband OFDM receiver in 65-nm CMOS. The proposed technique introduces a single multiplexer delay overhead and a configurable area overhead of M/i bits, where M is the number of memory rows and i is an integer from 1 to M, inclusive. The proposed strategy achieves a measured 0.15 dB gain improvement at a 2e-4 Quasi-Error-Free (QEF) BER in the presence of memory faults for an AWGN channel.

Demand for Wireless Local Area Networking (WLAN) has grown significantly during the past several years. WLAN systems need to support varying data rate applications and consume low amount of energy. This work presents a reconfigurable WLAN transceiver architecture that has the following key features: Four-stage pipeline struc¬ture to increase throughput and reduce dynamic power consumption; Multiple adjustable clocks to avoid excessive handshaking and buffering between pipeline stages, Dynamic reconfigurability to support different modes of operation; and Low reconfiguration cost, in terms of energy consumption and delay, to allow for efficient frame-by-frame adaptation. We have chosen the IEEE 802.11a standard as the demonstration platform, how-ever our ideas are extendable to other WLAN standards that are based on similar communication principles. For example, the popular IEEE 802.11g standard uses the same Orthogonal Frequency Division Multiplexing (OFDM) scheme as 802.11a. Consequently, both standards require somewhat similar data processing; i.e., our design techniques remain applicable. Our proposed architecture is prototyped on Xilinx FPGA, and simulations show a relatively low power consumption in comparison with other 802.11a baseband processors.

No description available.

International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California / Voyager ground aperture requirements for Neptune encounter in August 1989 exceed the expected capabilities of the Jet Propulsion Laboratory's Deep Space Network (DSN) 70- and 34-meter antennas. Agreements have been consummated with the National Science Foundation to array the National Radio Astronomy Observatory's Very Large Array in New Mexico and with the Commonwealth Scientific and Industrial Research Organization's Parkes Radio Telescope in Australia with the DSN. This technique, which was demonstrated during Voyager's Uranus encounter, will provide a greater return of imaging and non-imaging science data. The arrays consist of the normal facility receiving equipment at each location, augmented by special receiving, combining, recording, and monitor and control equipment. This equipment has been designed, is being implemented, and will be operated during the Neptune encounter to effectively double the available antenna aperture over the western United States and Australia.