Research Contributions:

WiFi, the Wireless LAN

The research program in wireless LAN at CWINS was established by Professor Kaveh Pahlavan in 1985 as the first research program of this sort in the United States. In 1986, the program was awarded the first NSF grant in modern wireless communications to start pioneering work on channel modeling, transmission and multiple access methods for wireless indoor networks.



IEEE Wireless Workshops

Third IEEE Workshop on Wireless LANs

From left to right: Kaveh Pahlavan, Workshop Chairman, Edson de Castro, Keynote Speaker, and Allen Levesque, Publicity Chair

Second IEEE Workshop on Wireless LANs

From left to right: Brian King, President of Proxim, Todd Smith, President of Aironet, Bruce Tuch, designer of WaveLAN, Paul Odlyzko, Chief Radio Architect, Motorola Radio Research Lab Craig Mathias, Principal of Farpoint, Kaveh Pahlavan, Workshop Chairman

First IEEE Workshop on Wireless LANs

From right to left: Charlie Bass, Cofounder of Ungermann-Bass, Kaveh Pahlavan, Workshop Chairman, and Phil Bello, pioneer of Statistical Radio Channel Modeling

Major Projects

Experimental Network with Wireless Connectivity (NSF)

  •  Herman G. Rotithor
  •  Sridhar Pingali
  • Kaveh Pahlavan
  •  John A. Orr
  • Ali Zaedi
  • Andy Messier
  • Jared Robinson
CWINS is significantly enhancing its research activities in wireless networks for multi-media applications with the support of an experimental wireless campus testbed that will be used to construct a wireless classroom environment. In this classroom, the instructor presents his/her material that is prepared on a personal computer through an electronic projector, and uses an electronic white board for handwriting. Multimedia services such as voice, text and bit-mapped images will be provided to students dispersed over a geographical area on the campus. In the past, CWINS has been recognized as a leader in wireless data communication research.

Channel Characterization, Tranmission, and Network Architecture for Wireless Indoor Radio Networks in Manufacturing Enviroment (NSF)

  • Kaveh Pahlavan
  • Tom Sexton
  • Steven Howard
  • Rajamani Ganesh
  • K. Zhang
The main objectives of this project are as follows:

(1) To perform wide band channel measurements for developing a statistical channel model and a computer simulation for indoor wireless radio networks. The measurement sites inculde GM munafacturing plant in Pramingham, Mass; Infinet, Inc., in N. Andover, Mass; Prudential Center in Boston, Mass and WPI.

(2) To analyze the throughput and delay characteristic of ALOHA like multiple accessing techniques in fading multipath indoor enviroments to investigate other multiple access techniques such as CSMA and BTMA for indoor radio networks; and to compare distributed and centeral networks for this application.

(3) To compare analysis of the performance based on various channel modeling techniques; to determine the data rate limitation in indoor enviroment if adaptive equalization is adopted at the receiver; to investigate methods to improve the data rate for spread spectrum techniques in fading multipath indoor channels.

Integrated Multi-layered Wireless LAN Testbed (NSF)

  • Kaveh Pahlavan
  • Emanuel Agu
  •  Rick Brown
  •  Sergey Makarov
  • Robert Kineck
  • John Orr

Using the IEEE 802.11 WLAN access points, PCMCIA WLAN cards, EKAHAU positioning software, and laptops acquired from the CNS support and our PROPSIM real-time channel simulator acquired from a DoD grant we have completed a novel laboratory testbed for performance evaluation of the indoor positioning systems operating based on RSS. This is the first laboratory testbed that is developed for performance monitoring of indoor positioning systems. The novel methodology adopted in this experiment uses our existing Ray-tracing software to identify location of the training points and measure the performance of the positioning software (in this case EKAHAU engine). The WLAN access points and a laptop with PCMCIA cards as well as the Ray-tracing software are connected to the real-time channel simulator that simulates the channel behavior between location of the access points and the mobile, specified in the Ray-tracing GUI. This innovative setup allows low cost repeatable performance analysis of indoor positioning systems. Our first publication in this field describes the architecture of the testbed and the preliminary results of performance evaluation that relates the density of the training points to the accuracy of the measurements.

Wireless LANs for UMTS (TEKES, Nokia and Sonera, Finland)

  • Kaveh Pahlavan
  •  Jaakko Talviti (CWC/U. of Oulu, Finland)
  •  Ali Zahedi,
  • Prashant Krishnamurthy,
  • Ahmad Hatami,
  • Yan Xu
  • Jari Vallstrom,
  • Roman Pichna,
  • Juha-Pekka Makela,
  • Mika Ylianttila
This project aims at the implementation of the high speed wireless LAN (WLAN) like services into the UMTS. It determines the specifications of the WLAN services that fit the UMTS and develops the algorithm and methodology for the multi-rate data services in which, transparent to the user application, the mobile data service falls back from the wireless LAN mode to a backup low speed mobile data service.

In its first stage, the project provides an overview of the existing wideband wireless local communication industry. It covers the evolution of the products and market as well as the emerging standardized technologies and other worldwide activities.

The work is done in close co-operation with Professor Jaakko Talvitie, Centre for Wireless Communications, University of Oulu, Finland

CDPD Performance Monitoring Tools (NYNEX Science & Technology)

  • Kaveh Pahlavan
The objective of this project was to design a Real-Time Cellular Packet Data (CDPD) Network Application Performance Monitor (NPM). A performance evaluation of the CDPD network was accomplished using the NPM and the results of this analysis were presented. Various benchmarking efforts and system performance analysis techniques were examined and incorporated into the software design of the NPM. Experimental throughput and response time data were gathered using the software tool on an actual CDPD network with one and two mobile subscribers. The experimental results reveal an upper bound on the performance of the CDPD network as well as the performance degradation with the addition of another CDPD user on the network.

Wireless Infrared (Jolt Ltd., ISRAEL)

  • Kaveh Pahlavan
  • Bernie Doeber
During the summer of 1996, we evaluated the performance of the Jolt UWIN807 long range 10 Mbps (LED based) ethernet transceivers in back to back laboratory tests. In this project we built an IR testbed, in order to perform bit error rate, packet error rate, and received signal strength vs. attenuation measurements in order to gain experience with and provide insight into the theory, design, testing, and operation of efficient high speed outdoor IR communication systems.