Teleseismic data recorded by broad-band seismic stations in the Swedish National Seismic Network (SNSN) have been used in a suite of studies of seismic wave conversion in order to assess the structure of the crust and upper mantle beneath the Baltic Shield. Signals of seismic waves converted between P and S at seismic discontinuities within the Earth carry information on the velocity contrast at the converting interface, on the depth of conversion and on P and S velocities above this depth. The conversion from P to S at the crust-mantle boundary (the Moho) provides a robust tool to constrain crustal thicknesses. Results of such analysis for the Baltic Shield show considerable variation of Moho depths and significantly improve the Moho depth map. Analysis of waves converted from S to P in the upper mantle reveals a layered lithosphere with alternating high and low velocity bodies. It also detects clear signals of a sharp velocity contrast at the lithosphere-asthenosphere boundary at depths around 200 km. Delay times of P410s, the conversion from P to S at the upper mantle discontinuity at 410 km depth, were used in a tomographic inversion to simultaneously determine P and S velocities in the upper mantle. The polarisation of P410s was also used to study anisotropy of the upper mantle. Results of these analyses are found to be in close agreement with independently derived results from arrival time tomography and shear-wave splitting analysis of SKS. The results presented in this thesis demonstrate the ability of converted wave analysis as a tool to detect and image geological boundaries that involve sharp contrasts in seismic properties. The results also show that this analysis can provide means of studying aspects of Earth’s structure that are conventionally studied using other types of seismic data.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / This paper discusses the design and performance of the FM/PM/BPSK "personal computer card-based" receiver. In PSK, a carrier recovery technique must be used for signal demodulation. Costas loop is a well known method and is the basis in the design of the BPSK demodulation. A new design approach employing digital Box Car arm filters is used to improve receiver performance and flexibility. Detail design and performance of the digital Costas loop will be explored in a later section. A classical technique is employed for Phase demodulation with the use of tracking Phase Lock Loop. Frequency demodulation is designed around a simple, single FM discriminator IC.

This thesis examines the performance of the support vector machine and the random forest models in the context of binary classification. The two techniques are compared and the outstanding one is used to construct a final parsimonious model. The data set consists of 33 observations and 89 biomarkers as features with no known dependent variable. The dependent variable is generated through k-means clustering, with a predefined final solution of two clusters. The training of the algorithms is performed using five-fold cross-validation repeated twenty times. The outcome of the training process reveals that the best performing versions of the models are a linear support vector machine and a random forest with six randomly selected features at each split. The final results of the comparison on the test set of these optimally tuned algorithms show that the random forest outperforms the linear kernel support vector machine. The former classifies all observations in the test set correctly whilst the latter classifies all but one correctly. Hence, a parsimonious random forest model using the top five features is constructed, which, to conclude, performs equally well on the test set compared to the original random forest model using all features.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / TSI TelSys, Inc. is in the process of developing a production level, continuously tunable satellite receiver designed to support multiple high data rate, low earth and geostationary orbit missions in the 20 Mbps to 800 Mbps composite QPSK data rate range. This paper will evaluate market demands on satellite receivers and outline receiver design technique as a solution to high rate, multi-mission support.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Within the industry, telemetry receivers are used in ground-based telemetry receiving stations to receive telemetry data from air or space-based sources. Equipment for the typical telemetry application is widely available. But when requirements create the need for a space-based telemetry receiver to uplink data from the ground, what are the choices for equipment? In such situations, adapting COTS equipment may present the only solution to meet delivery and budgetary constraints. The first part of this paper provides technical and contractual points a COTS supplier needs to consider when bidding on a COTS contract. The second part of this paper covers a project concerned with modification of a general-purpose ground telemetry receiver for use on the International Space Station. The information within the paper is useful to other engineers and companies considering contracts to modify COTS equipment for use on Shuttle or other space-based projects.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Three-channel monopulse tracking receiver systems are commonly used for high performance tracking of satellites, missiles, or aircraft to maximize the reception of data. Typically, the receiver in such systems are custom designed for their end purpose. This results in a high cost to cover the development, service, and support of a highly specialized piece of equipment. This paper covers the requirements and performance of a 3-channel monopulse tracking receiver assembled from commercial-off-the-shelf (COTS) equipment. Such a system provides an option for designing or upgrading tracking stations with the lower cost, larger support base, and greater system configuration choices that are available with COTS equipment.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes an approach to the implementation of an IF sampling digital receiver for low data rate command and telemetry applications in the NASA Goddard Spaceflight Tracking and Data Network (STDN) and Air Force Space-Ground Link System (SGLS). The digital design is targeted for an FPGA-based implementation and was written entirely in VHDL. Several size and clock reduction techniques are described which were utilized due to limited gate-array resources and power. The system-level design architecture is described followed by a discussion of algorithms and performance of critical stages in the receiver chain. Bit error performance of the prototype receiver is also presented. Finally, although this design is specifically targeted for a narrowband command and telemetry application, the methodology forms the basis of a configurable receiver for higher data rate applications.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / High dynamic and multi-channel digital GPS receiver can handle the signals with high dynamic range, low S/N ratio and refresh data quickly. A hardware design of high dynamic GPS digital receiver is given. Based on analysis of the effect that high dynamic movement makes on the receiving signals, a scheme of fast-acquisition high dynamic GPS receiver is presented. Exact reckoning of the orbit parameters and the satellite clock parameters are integrated with appropriate algorithms. A DDLL is used to precisely estimate the C/A code delay, a CPAFC loop and a Costas loop to precisely estimate the carrier frequency and phase. The DDLL is assisted with carrier phase. The experimental results show that the receiver meets the design request.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Delay Mapping Receiver (DMR) is used for receiving and processing the reflected GPS signal to get the information of sea surface wind by recording and matching the data with the theoretical model. The hardware architecture and software design are described in detail in this paper. The test results at near sea of Tianjin of China are provided, which prove that the design of DMR is successful and the collected data are useful for the sea surface wind measurement.

Wireless devices have become an integral part of our everyday lives. Cell-phones, PDA's, Wi-Fi enabled laptops, smart homes and appliances, and automated highway systems are some of the examples of wireless devices and networks in common use. More and more applications and functionalities are constantly being added to these devices, and to support these new applications high data rate communication is required between the wireless devices. Achieving high data rates with wireless communication is impeded by severe fluctuations in the received signal strength (called fading) due to mobility, the exponential attenuation of signal power with distance (called path loss), and interference due to simultaneous transmissions by different users at the same time or over same frequency band. Two of the promising techniques to mitigate the effects of fading, path loss, and interference are: using multiple antennas at the transmitter and receiver, and employing extra nodes (called relays) in between the transmitter and its receiver to relay the transmitter's message to its receiver. This dissertation identifies the optimal transmit and receive strategy with multiple antennas that maximizes the transmission capacity of an ad-hoc wireless network. The transmission capacity is defined as the maximum number of transmitter-receiver pairs that can simultaneously communicate under a per transmission quality of service constraint. This dissertation also presents novel relay transmission strategies for multiple antenna equipped relay based communication that achieve near optimal performance, with Shannon capacity and diversity-multiplexing tradeoff (DMT) as the performance metrics. The Shannon capacity is defined as the maximum rate of reliable communication, while the DMT characterizes the maximum diversity gain for a given value of multiplexing gain in a multiple antenna system. DMT is used as the benchmark, since transmission strategies that meet the DMT are guaranteed to leverage both the advantages of multiple antenna systems. / text