The activity monitoring of humans is a very active area
of research and a lot of activities are going on. There
are many parts which are to be considered in a global
way: (1) types of sensors to be used; (2) type of wireless
protocols to be employed; (3) monitoring of activities to
be considered; (4) methodology to determine activities or
extraction of important features; (5) design and development
of small, light-weight, powerful and low-cost smart sensor
nodes; (6) harvesting of energy for normal operation and
communication; (7) ability to be used with the present day
mobile devices; (8) flexible to configure the system for a new
user without much difficulty.