Towards fully integrated wideband transceivers: fundamental challenges, solutions and future

Abstract

Design considerations of a generic wideband communication system differ significantly from its narrowband counterpart. In a wideband system, intermodulation distortion increases significantly, as the signal propagates through various active stages of RF/analog signal processing blocks. Thus, in contrary to the narrowband approach, it requires careful optimization of noise and linearity for a given power consumption. Many of these systems today utilize multicarrier modulation approach to provide robustness for dynamic wireless environment. Multicarrier modulation also aids the development of direct conversion transceivers leading to further optimization of signal processing algorithms at the Baseband. In this paper, we would illustrate the architectural trade-off and design consideration of fully integrated direct conversion transceivers in standard silicon based processes. Fundamental considerations of power, linearity, effect of out-ofband blockers, coexistence with other standards would be addressed for a direct conversion tTWB transceiver based on multi-band OFDM approach.

A Frequency Triplexer for Ultra-Wideband Systems Utilizing Combined Broadside- and Edge-Coupled Filters

“…In pulsed multi-band systems this group delay variation might cause degradation of system performance. However, in orthogonal frequency division multiplexing systems the group delay impact on the system level performance should be marginal [29].…”

“…UWB has gained popularity in recent years [21]- [29]. The interest for high speed and short range wirelesscommunication has been one of the major driving forces behind the UWB development [22]- [25].…”

“…One is based on the direct sequence spread spectrum technique, supported by the UWB-forum [24], [27]- [28]. The other is based on the multi-band orthogonal frequency division multiplexing technique (Also known as "Wimedia UWB", supported by Wimedia alliance) [25]- [26], [29]. The multi-band specification divides the frequency spectrum into 500 MHz sub-bands (528 MHz including guard carriers and 480 MHz without guard carriers, i.e., 100 data carriers and 10 guard carriers).…”

“…Three sub-bands are mandatory, centered at 3.432, 3.960, and 4.488 GHz, respectively [24]- [28]. Orthogonal frequency division multiplexing has the advantage of inherent robustness against gain, phase, and group delay variations [29], [30].…”

Circular Dipole Antenna for Mode 1 UWB Radio With Integrated Balun Utilizing a Flex-Rigid Structure

“…One is based on the direct sequence spread spectrum technique [4], [7]- [8]. The other is based on the multi-band orthogonal frequency division multiplexing technique (Also known as "Wimedia UWB", supported by Wimedia alliance) [5]- [6], [8]- [9]. The multi-band specification divides the frequency spectrum into 500 MHz sub-bands (528 MHz including guard carriers and 480 MHz without guard carriers, i.e., 100 data carriers and 10 guard carriers).…”