The document summarizes a student project to design and implement an ultra-wideband impulse radio transmitter using a 0.13μm CMOS chip. Key points: - The team designed their own printed circuit board to test the chip, using an FPGA to control the chip. - The chip supports three modulation techniques: OOK, PPM and BPSK using frequency, width and phase modulation respectively. - Testing showed the chip can selectively transmit in the 3-8GHz range as desired. - Future work includes designing a receiver and new version of the transmitter chip.

1. George Lee, Lulan Shen and Rabia Rassil, supervised by Professor Frederic Nabki
Department of Electrical and Computer Engineering, McGill University, Montreal, Canada
Ultra Wideband Impulse Radio Transmitter Characterization
Acknowledgments
Conclusions
Background
Introduction Design Results
.
Improvements
Reference
Our design project is to design and implement a low
power functional UWB transmitter using a 0.13µm CMOS
chip. We designed and fabricated our own PCB, while
using the FPGA to send the input control signals to the IC
chip. Our IC chip is a strong candidate for short distance
wireless data rate transmissions such as Bluetooth.
OOK correlates the number
of pulses generated for a
certain period to the actual
value.
Pulse Position Modulation
On/Off Switching Key
PPM uses the position for a
certain period to encapsulate
the information. When the
pulses are in the 1st half of
the period, the data value
equal to 1. The 2nd half of the
period equals to a value of 0.
Pulse Generator : Varies the pulse width
VCRO: Generates modulated pulses
Amp S2D: Amplifies and shifts by 180°
Power Cycling: Turns off circuit when not transmitting
Binary Phase Shift Keying
BPSK uses trinary logic 1, 0 and -1. BPSK uses phase
shifting by 180° to reverse the pulse and implement -1.
Transmitter
Transmitter PCB and Layout
PCB design contains VHDL connector, transmission line,
buffer, biasing and power supply. We reduced the
number of pins from 64 to 28 pins. Most of the pins are
used for power supply and biasing.
The frequency modulation is shown with control bits 7 and
3 at frequencies of 3.2GHz and 6.1GHz.
The width modulation control bits are 0 and 15 with pulse
widths of 0.4 and 1.4ns.
Frequency Modulation
Width Modulation
Phase Modulation
Power Spectral Density
We are able to select and
reject a specific range of
frequency such as from 4 to
6GHz while allowing all
other frequencies, shown in
below on the right. We want to thank Rabia Rassil, Professor Frederic Nabki’s
student, for helping us with understanding the IC chip,
teaching us PADS 9.5, and supervising the project.
The Roger’s transmission
line increased the output
signal’s amplitude by 65%.
When the transmitter sends at
a higher data rate, the power
consumption increases linearly.
 Our IC chip has three types of fully functional
modulations: OOK, PPM and BPSK that uses
frequency, width and phase modulation, respectively.
 As shown in the PSD spectrum, we are able to choose
to transmit at our desired frequencies from 3 to 8GHz.
The Institution of Engineering and Technology. (2012.) Ultra
Wideband.Available:http://www.theiet.org/resources/journals
/eletters/4811/non-stop-rejection.cfm
Future Work
 Implementing a functional UWB IR receiver
 Design a newer version of the IC chip for the transmitter
 Academic paper with the new results of the IC chip