On 60GHz Wireless Communication Systems

The consumer of the telecommunication services of tomorrow will expectto receive the same services in a wireless fashion as he today receivesfrom a fixed network. These services require reliable high data rate. Thisthesis forms part of the 4:th Generation Wireless (4GW) project in thePersonal Computing and Communication (PCC) program, focusing on the keyfactors that are expected to limit the evolution of future wireless communicationsystems. Using a scenario based approach, this work presents a set of possible"telecom futures". Key technical & economical research issues are derived.One of the important requirements in the design of an air interface isits flexibility. User deployed access points and self-planning capabilitiesare the underlying factors that will make the 4GW infrastructure economicallyviable. Indeed, public and private networks are expected to coexist, bothoffering high bit rate communication and a broad range of services.It is shown in this thesis that an Orthogonal Frequency Division Multiplexing(OFDM) based modulation is a good candidate for broadband wireless systems.This scheme is well suited for transmitting high data rates in frequency-selectiveslow fading channels, and, in the case of a properly dimensioned system,the fading experienced by each subchannel becomes flat.The 60 GHz frequency band has been identified as one of the potentialhigh bit-rate bands with 5 GHz of unlicensed bandwidth with a target bitrateof more than 100 Mbit/s per user in offices, shopping-malls and downtownareas. As part of this work, we aim to understand the fundamental issuesinherent to the use of millimeter wave bands for wireless communica tionsystems. Propagation, interference and shadowing issues are presented.Evaluation of DQPSK-OFDM shows the impact of the 60 GHz channel on a givensystem. In addition, we evaluate system performance using Monolithic MicrowaveIntegrated Circuit (MMIC) components developed at Chalmers and identifythe critical characteristics of microelectronic components for the proposedscheme