An Ultra-Wideband Sensor Node Development with Dual-Frequency Band for Medical Signal Monitoring - Ultra Wideband Wireless Body Area Networks - page 97

RF Module

ANT

BPF
(3.5-4.5 GHz)

IR-UWB baseband
pulses

LPF
(DC-1.4 GHz)

Mixer

AN D

Data from the
micro-controller

VCO (4 GHz)

Fig. 5.14 The block diagram of the IR-UWB RF section

Fig. 5.15 Frequency spectrum of VCO based sensor node at a UWB pulse generator output
b 1.4 GHz LPF output c mixer output d 3.5-4.5 GHz BPF output

output of the mixer in order to contain the UWB signals within the 3.5-4.5 GHz
band.
Figure 5.16 depicts the hardware implementation of the UWB RF section on
the sensor node PCB. Co-planar wave-guide transmission lines with 50 X
impedance matching are used for all the RF tracks of the circuit. Table 5.2 shows
major components used in the design of the IR-UWB RF section. The VCO is