Ephraim Bemis Flint

Wide band AC power line characterization

This paper presents data characterizing the household AC power line in the 1-60 MHz band. Two types of measurements were performed: transmission and noise sampling. The transmission measurements were done by using the impulse channel sounding method, so both the line attenuation and the delay spread were obtained. The noise measurements include: power line background noise, appliance noise, and noise sampled over a 24 hour period. Statistical characteristics of the delay spread, frequency response and noise can be extracted from the data and used in the design of AC power line based communications systems.

Developing integrated antenna subsystems for laptop computers

The design, development, testing, and integration methodology for antennas integrated into laptop computers is described. Two key parameters are proposed and discussed for laptop antenna design and evaluation: standing wave ratio (SWR) and average antenna gain. A novel averaging technique was developed and applied to these to yield a measurable, repeatable, and generalized metric. A prototype antenna was built using this methodology, and measurements indicate that the resulting design attains both performance and cost targets. A PC-card-version wireless system is also discussed and compared with the integrated one. The impact of the antenna on the overall wireless system is studied through a link budget model.

A high-density, four-channel, OEIC transceiver module utilizing planar-processed optical waveguides and flip-chip, solder-bump technology

An optoelectronic transceiver module is described consisting of a four-channel AlGaAs integrated laser/monitor transmitter and a four-channel GaAs MESFET integrated detector/preamp receiver. The optoelectronic chips are flip-chip, solder-bump bonded to a substrate containing electrical wiring and planar-processed optical waveguides. The optical waveguide layer serves two purposes: the routing of optical signals, as well providing mechanical registrations for the optoelectronic chips and fiber-optic ribbon connector. The work described here demonstrates one approach to high-density, optoelectronic array packaging compatible with existing high-performance electronic packaging technology. >

Optical Fiber Coupling Approaches For Multi-Channel Laser And Detector Arrays

Two fiber-optic coupling approaches are described for providing accurate and simultaneous alignment between four multimode fibers and a four-channel GaAs laser and detector array. The fiber-detector array coupling approach provides less than 0.2 dB loss with better than -20 dB optical crosstalk between adjacent channels. The fiber-laser array coupling approach provides -3 dB coupling loss for each of four fiber-laser channels.

GaAs fiber-optic modules for optical data processing networks

A high-speed, highly integrated fiber-optic data communications link is described. It consists of a transmitter module containing a GaAs integrated circuit and a laser array with fiber array pigtail, and a receiver module containing a GaAs OEIC with a fiber array pigtail. The performance of the link at 1 Gb/s is presented with emphasis on the crosstalk and noise issues with those high levels of integration. Measured error rates as low as 10/sup -15/ confirm that these highly integrated link adapters are suitable for use in data processing networks. >

A new dual-band antenna for ISM application

This paper presents dual-band antenna structures for portable applications. The antenna can be stamped from sheet metal or manufactured on a single-sided PCB. No additional impedance matching is necessary. The antenna structure is simple, but it has high efficiency and reasonable SWR bandwidth.

Wide band home phone line characterization

This paper presents data characterizing the household phone line in the 1-60 MHz band. Two types of measurements were performed: transmission and noise sampling. The transmission measurements were done by using the impulse channel sounding method, so both the line attenuation and the delay spread were obtained. The noise measurements include: phone line background noise, phone noise, and noise sampled over a 24 hour period. Statistical characteristics of the delay spread, frequency response and noise can be extracted from the data and used in the design of phone line based communications systems.