Biomedical Engineering Reference
In-Depth Information
(a)
3.3 V
a
3.3 V
b
3 V
c
3 V
d
400 mV
e
(b)
f
Demodulated
data bits
OOK
modulated
NB RF signal
g
Fig. 5.23 a Waveforms taken at various points of the UWB transmitter stion b data reception at
the narrow band receiver (See Fig.
5.22
for respective reference points related to the waveforms
in the sensor node design)
(2) Narrow band transmitter
The 433 MHz ISM band transmitter transmits the control messages originated
from the FPGA on the narrow band channel.
(3) Sampling and data processing unit
The sampling and data processing unit consists of an ADC and a FPGA. It is
responsible for the operation of the MAC protocol at the coordinator node.
