Spectral efficiency in reference-signal-assisted low-power wireless communication

Expressions relating spectral efficiency, power and Doppler spectrum are derived for low-power Rayleighfaded wireless channels with proper complex signaling. Noside information on the state of the channel is assumed at the receiver. Rather, periodic reference signals are postulated inaccordance with the functioning of most wireless systems. In contrast with most previous studies, which relied on block-fading channel models, a continuous-fading model is adopted. This embeds the Doppler spectrum directly in thederived expressions thereby imbuing them with practical significance.

Fading models and metrics for contemporary wireless systems

The purpose of this paper is to examine (1) some of the models commonly used to represent fading,and (2) the information-theoretic metrics most commonly used to evaluate performance over those models. We raise the question of whether these models and metrics remain adequate in light of the advances that wireless systems haveundergone over the last two decades. Weaknesses are pointedout, and ideas on possible fixes are put forth.

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2006.

Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2006

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2007.

Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2007

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2008.

Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2008

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2009.

Audit report on the Wireless E911 Emergency Communication Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2009

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2010.

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2010

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2011.

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2011

Wireless E911 Emergency Communications Fund Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense independent auditor's reports, basic financial statements and supplementary information, June 30, 2012.

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2012

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2013

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Homeland Security and Emergency Management Division of the Iowa Department of Public Defense for the year ended June 30, 2013

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Department of Homeland Security and Emergency Management for the year ended June 30, 2014

Audit report on the Wireless E911 Emergency Communications Fund of the Iowa Department of Homeland Security and Emergency Management for the year ended June 30, 2014

Secure many-to-one communications in wireless sensor networks

Wireless Sensor Networks (WSN) are formed by nodes with limited computational and power resources. WSNs are finding an increasing number of applications, both civilian and military, most of which require security for the sensed data being collected by the base station from remote sensor nodes. In addition, when many sensor nodes transmit to the base station, the implosion problem arises. Providing security measures and implosion-resistance in a resource-limited environment is a real challenge. This article reviews the aggregation strategies proposed in the literature to handle the bandwidth and security problems related to many-to-one transmission in WSNs. Recent contributions to secure lossless many-to-one communication developed by the authors in the context of several Spanish-funded projects are surveyed. Ongoing work on the secure lossy many-to-one communication is also sketched.

MIMO Wiener model identification for large scale fading of wireless mobile communications links

The large scale fading of wireless mobile communications links is modelled assuming the mobile receiver motion is described by a dynamic linear system in state-space. The geometric relations involved in the attenuation and multi-path propagation of the electric field are described by a static non-linear mapping. A Wiener system subspace identification algorithm in conjunction with polynomial regression is used to identify a model from time-domain estimates of the field intensity assuming a multitude of emitters and an antenna array at the receiver end.