International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Data Encryption Standard (DES) was developed in 1977 by IBM for the National Bureau of Standards (NBS) as a standard way to encrypt unclassified data for security protection. When the DES decrypts the encrypted data blocks, it assumes that there are no bit errors in the data blocks. It is the object of this project to determine the Hamming distance between the original data block and the data block after decryption if there occurs a single bit error anywhere in the encrypted bit block of 64 bits. This project shows that if a single bit error occurs anywhere in the 64-bit encrypted data block, a mean Hamming distance of 32 with a standard deviation of 4 is produced between the original bit block an the decrypted bit block. Furthermore, it is highly recommended by this project to use a forward error correction scheme like BCH (127, 64) or Reed-Solomon (127, 64) so that the probability of this bit error occurring is decreased.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The impact of multipath fading parameters on the probability of error for Offset QPSK (OQPSK) is derived. The multipath fading channel is modeled using the aeronautical telemetry channel model [1-2]. Expressions for the probability of bit error are derived that are a function of the multipath model parameters. The expressions are shown to agree with computer simulations and show that a strong multipath reflection with a short delay causes much more degradation than a weak multipath reflection with a long delay.

International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / The first Indian Remote Sensing Satellite was launched on 17th March 1988 from a Soviet Cosmodrome into a 904 Km Polar Sunsynchronous orbit. The data transmission from the satellite is at 5.2 Mega Bits/sec in S-Band and 10.4 Mega Bits/sec in X-Band. The payload data is formatted into custom made 8328 words format. A programmable unique versatile frame sync and Decommutation unit has been developed to test the data from the data handling system during its various phases of development. The system works upto 50 Mega Bits/sec and can handle frame sync code length upto 128 bits and a frame length of 2 Exp 20 bits. Provision has been made for programming the allowable bit errors as well as bit slippages, using a front panel setting. This paper describes the design and implementation of such a high bit rate frame synchroniser developed specially for IRS Spacecraft application. It will also highlight the performance of the system.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Telemetry receiving sites at missile test ranges almost always use polarization diversity to maximize the quality of the telemetry signals collected from missiles during developmental tests. If the sites are operating optimally, their sensitivity should be independent of received polarization. In this paper a technique to test the sensitivity of each receiving site is presented that involves radiating from a central location with selectable polarization and precise power level. Results of testing five telemetry sites are presented and compared with performance predicted through link analysis using site G/T and location information.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / End-to-End testing is a tool for verifying that Range Telemetry (TM) System Equipment will deliver satisfactory performance throughout a planned flight test. A thorough test verifies system thresholds while gauging projected mission loading all in the presence of expected interference. At the White Sands Missile Range (WSMR) in New Mexico, system tests are routinely conducted by Range telemetry Engineers and technicians in the interest of ensuring highly reliable telemetry acquisition. Even so, flight or integration tests are occasionally halted, unable to complete these telemetry checks. The Navy Standard Missile Program Office and the White Sands Missile Range, have proactively conducted investigations to identify and eliminate problems. A background discussion is provided on the serious problems with the launcher acquisition, which were resolved along the way laying the ground work for effective system testing. Since there were no provisions to test with the decryption equipment an assumption must be made. Encryption is operationally transparent and reliable. Encryption has wide application, and for that reason the above assumption must be made with confidence. A comprehensive mission day encrypted systems test is proposed. Those involved with encrypted telemetry systems, and those experiencing seemingly unexplainable data degradations and other problems with or without encryption should review this information.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The bit rates of telemetry systems are increasing rapidly. Higher bit rates occupy more spectra and result in decreased link margin. The major signal parameters that affect the spectral occupancy and bit error probability (BEP) of binary pulse code modulation (PCM)/frequency modulation (FM) signals are the bit rate, code, premodulation filter, and peak deviation. The measured spectral occupancy is also affected by the spectrum analyzer (or other measurement equipment) settings. Additional parameters that affect the BEP include the receiver intermediate frequency (IF) filter, the FM demodulator, and the bit detector. This paper will present the effects of these parameters on the measured 99% and -60 dBc bandwidths and the BEP of binary PCM/FM telemetry signals. Normalized BEP and bandwidth curves will be presented.

No description available.

Most of the previous research on multistage interference cancellation receivers for Code Division Multiple Access (CDMA) systems has relied on the use of simulation techniques for performance evaluation. This thesis formulates a model for an adaptive multistage interference cancellation receiver within a CDMA system to be employed at the cellular radio base station. A closed form expression for the probability of bit error for this adaptive multistage interference cancellation receiver is derived, using a Gaussian approximation for Multiple Access Interference (MAI). The Bit Error Rate (BER) after any stage of interference cancellation can be computed from the signal to noise ratio, number of users and processing gain of the CDMA system. The BER expressions are extended to derive asymptotic limits on the performance of interference cancellation as the number of cancellation stages approaches infinity, demonstrating a fundamental limit on the performance improvement that can be expected from any multistage interference cancellation scheme. Furthermore, the analysis quantifies conditions under which interference cancellation may degrade performance. This thesis also extends a software implementation of the Multistage Rake receiver for a wide range of channel models including Gaussian noise, MAI, multipath propagation and near-far effects. Simulation results demonstrate the robustness of the Multistage Rake receiver to near-far effects and manifold capacity improvement compared to conventional demodulation techniques. / Master of Science

Physical-Layer Network Coding (PNC) is a promising technique that has great potentials for improving the achievable data rates of end-to-end flows through higher packet transmission rates, thereby increasing the overall network throughput. In this thesis, we study the performance of the PNC transmission techniques for unidirectional end-to-end flows in multi-hop wireless networks, and compare it with that of the traditional transmission techniques. We first derive the bit-error rate (BER) that the PNC transmission technique achieves. Then, using the derived BER, we evaluate and quantify the achievable network throughput under both the PNC transmission technique and the traditional technique, where the network throughput is measured as the aggregate/sum of all end-to-end flows' achievable data rates in the wireless network. Using extensive simulations, we show that PNC increases the overall achievable end-to-end flow throughput in multi-hop wireless networks, especially under medium to high signal-to-noise ratios. / Graduation date: 2012

With the fast adoption of LTE and IEEE 802.11N, more devices are employing multiple antennas to boost the data rate and reliability of the communication link. Traditionally, fixed antennas are used in such devices. In recent years, reconfigurable antennas have been sought out to further boost the performance, which can adaptor to the changing wireless channel by altering their radiation characteristics, and maintain or exceed the performance of fixed antennas. This thesis studies the possibility of performance increase using pattern reconfigurable antennas as receivers. Their performance potential was first estimated using simulations, and then demonstrated using two electrically steerable passive array radiator (ESPAR) antennas against a pair of monopole antennas on a hardware bit error rate (BER) testbed. The former produces equal performance in BER with certain pattern combinations and excels in theoretical capacity with substantial lead making pattern reconfigurable antenna a potent option as receiver in MIMO-related applications.