On 60GHz Wireless Communication Systems
The consumer of the telecommunication services of tomorrow will expect
to receive the same services in a wireless fashion as he today receives
from a fixed network. These services require reliable high data rate. This
thesis forms part of the 4:th Generation Wireless (4GW) project in the
Personal Computing and Communication (PCC) program, focusing on the key
factors that are expected to limit the evolution of future wireless communication
systems. 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 is
its flexibility. User deployed access points and self-planning capabilities
are the underlying factors that will make the 4GW infrastructure economically
viable. Indeed, public and private networks are expected to coexist, both
offering 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-selective
slow 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 potential
high bit-rate bands with 5 GHz of unlicensed bandwidth with a target bitrate
of more than 100 Mbit/s per user in offices, shopping-malls and downtown
areas. As part of this work, we aim to understand the fundamental issues
inherent to the use of millimeter wave bands for wireless communica tion
systems. Propagation, interference and shadowing issues are presented.
Evaluation of DQPSK-OFDM shows the impact of the 60 GHz channel on a given
system. In addition, we evaluate system performance using Monolithic Microwave
Integrated Circuit (MMIC) components developed at Chalmers and identify
the critical characteristics of microelectronic components for the proposed
4:th Generation Wireless (4GW)