International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A composite PCM/FM+FM/FM system combines the spectral efficiency of the analog system with the accuracy of a PCM system when needed for specific sensors and allows the direct transmission of binary computer words if necessary. A PCM/FM+FM/FM system combines the bit sequence with the modulated subcarriers at baseband and the resultant modulates the carrier. In the design of the composite system it is of importance to determine the impact of the subcarriers on the bit error rate of the bit sequence and to determine the degradation of the output signal-to-noise ratio of the subcarrier channels caused by the bit sequence.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 789-809 (v. 3)).

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A typical PCM/FM system is designed for a peak to peak carrier deviation of 0.7 times the bit rate of the PCM data. This value of PCM data deviation has been shown to be optimum for both PCM/FM [1] and PCM/FM+FM/FM [2] systems. However, the optimum deviation of the carrier by the FM subcarrier for a PCM/FM+FM/FM system is dependent upon the specific subcarrier type and required subcarrier signal to noise ratio at the receiver output. This paper introduces a simple method to calculate the optimum deviation of the carrier by FM subcarriers for a PCM/FM+FM/FM system. The method developed is used to calculate the optimum value of subcarrier deviation for two sample PCM/FM+FM/FM systems when IRIG constant bandwidth channels are used as FM subcarriers. The calculated optimum values of FM subcarrier deviation of the carrier, subcarrier mod index, are utilized in a companion paper to study the performance of PCM/FM+FM/FM systems [3]. The work presented herein can be extended to calculate the optimum deviation of the carrier by FM subcarriers for any PCM/FM+FM/FM system.

Abstract The interaction between the multilayer of Antiferromagnetic(AFM)/ Ferromagnetic(FM) film have been one of the focal point in scientific and technology. In our preliminary result the enhancement on the low field magnetoresistance of AFM-La0.67Sr1.33MnO4 and FM-La0.67Ca0.33MnO3 mixture is obvious. It is, therefore, worthwhile to make it into a form of multilayer as the tunneling magnetoresistance (TMR) structure. This project was planed to start at a bilayer film of AFM-La0.67Sr1.33MnO4/ FM-La0.67Ca0.33MnO3 on SrTiO3(100) substrate by an off-axis RF sputtering system. Experiment at high temperature region (T¡Ö70K) exhibits normal colossal magnetoresistance (CMR) behavior. A small cusp appears in R-T curve between 50~70K which is believed due to the quantum fluctuation initiated from AFM layer acted on the AFM/FM interface. However, the MR properties at this region shows abnormal phenomenon. The MR curve strongly depends on the sample posture during measurement when the relative geometry between the applied field, the applied current and the sample surface is fixed. The reason of this abnormal phenomenon is not clear yet and worth for further study .

Invented in 1935, Frequency Modulation (FM) is one of the most widely used analog modulation techniques in telecommunications. Since its inception FM radio has been used for high-fidelity music and speech broadcasting, offering excellent sound quality, signal robustness and noise immunity. Recently, FM Radio has witnessed an explosion of interest for its applications in mobile and personal media players (PMP). However, the traditional FM requires a long antenna, such as a wired headphone, which limits its usefulness for many users who do not carry a wired headset. This paper introduces FM solutions that enable the antenna to be integrated or embedded inside the device enclosure, thereby optimizing the end solution for portable consumer electronics. / text

Thesis (M.A.)--University of Wisconsin. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 142-144).

Typescript (photocopy). / Digitized by Kansas Correctional Industries

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / With recent developments in telemetry transmitter technologies, significantly greater DC to RF power efficiencies can be achieved. These new high efficiency transmitter designs may impact overall system design trade-offs by reducing the system size and weight requirements for batteries, heat sinks, and cabling. Furthermore, these fully DC isolated, next generation ARTM Tier 0, I and II enabled devices offer unique options to the platform designer in EMI/EMC control and system design. Advanced manufacturing techniques coupled with adaptive microprocessor control promises enhanced functionality, improved performance and reduced unit costs. The paper presents the performance of a new, high efficiency, telemetry transmitter topology and the possible system benefits involved with the application of this advanced transmitter technology within modern and legacy telemetry platforms. Specific sub-assembly circuit design techniques will be discussed and compared with prior design approaches.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Much modem telemetry is transmitted in a digital format and to be compatible with existing range equipment the digital data is impressed on the carrier using FM modulation. The receiving system in common use employs an FM limiter/discriminator as a detector followed by an integrate and dump matched filter for bit detection. This system has been studied by previous authors [1] and it is well known that in the absence of frequency uncertainty the optimum transmission parameters consist of a modulation index of .7 (peak-to-peak deviation divided by the bit rate) and an IF filter bandwidth equal to the bit rate followed by a limiter discriminator. In many cases, there is a need for some small amount of analog telemetry transmission in addition to the digital data discussed above. In these cases it is common practice to include analog subcarriers on the main carrier with the digital data modulating the carrier at baseband, the resulting system is called PCM/FM + FM/FM. These hybrid analog/digital systems are the subject of this paper. In particular this paper addresses the performance of these systems through simulation using the Block Oriented System Simulator (BOSS) from Comdisco and with analytical techniques to obtain the BER versus SNR curves for these systems. The simulation is used over a wide range of parameters to find the optimum values of modulation index and IF bandwidth for these systems.