Subsystems and Systems

RSS

This document details how to specify harmonics for a ZigBee FEM. It reviews the requirements from the different regulatory standards, analyzes through simulation harmonics content of offset quadrature phase-shift keying (OQPSK) spread spectrum modulation and evaluates the effects of the measurement bandwidth and detector on the harmonics level of both sine and ZigBee waveforms. Finally, measurement data is provided to illustrate the simulations results.

RF signals transmitted via wireless mobile channels suffer from several effects like smallscale fading and signal dispersion and distortion. This paper reviews these effects and simulates Rayleigh and Rician multipath fading channels with a comparison between them in terms of the effect of RF signal random fluctuations, average received signal level, outage probability, and effect of Doppler shift. In addition to that, signal dispersion occurring to pulses transmitted through these types of channels has also been discussed and simulated.

The choice and placement of a RFID tag on a product requires an investigation to determine optimal performance. The current technology of HF tags is focused on the mass production of low cost paper thin tags that have maximized read range performance perpendicular to the broad plane of the tag. Incorporating both these tag designs for use within the RFID architecture allows for flexibility of product placement and orientation while maintaining optimum performance.