1. Generation of CS-UWB DDL
June 2005
Generation of CS-UWB
CS-UWB can be generated by passing a pulse signal through a distributed delay line（DDL） such as a SAW DDL.
Frequency
DDL
Time
Amplitude
Amplitude
Time
Pulse signal
Frequency
Li, Takizawa, Sasaki, Hara, Itami, Ikegami, Kohno, NICT

2. Correlated processing
June 2005
Correlated processing
Correlated processing produces not only high precision ranging but also robustness against noise and multipath.
Correlated processing
Correlator output
B: 3-dB bandwidth of chirp
T: time interval of chirp
Time shift[s]
The wide the bandwidth, the sharp the peak.
Li, Takizawa, Sasaki, Hara, Itami, Ikegami, Kohno, NICT

3. Overall Block Diagram With Optional CS
June 2005
Overall Block Diagram With Optional CS
Transmitter
Comm.data
BW = 500MHz or 2GHz
Coding &
modulation
Spreading
Pulse
shaping
CHIRP GA
Ranging data
Local oscillator
Receiver
Pre-Select
Filter
LPF GA
1 or 2-bit ADC
Decision/
FEC decoder
Comm.data
LNA
De-
CHIRP
LPF GA
1 or 2-bit
ADC
Ranging data I
Local
oscillator
Ranging processing
Sync.
Peak detection Q
Time base
Calculation
Additional circuits to DS-UWB as an option
Li, Takizawa, Sasaki, Hara, Itami, Ikegami, Kohno, NICT

4. Simulation results for SOP
June 2005
Simulation results for SOP
Li, Takizawa, Sasaki, Hara, Itami, Ikegami, Kohno, NICT

5. Advantages of Chirp Signaling
June 2005
Advantages of Chirp Signaling
High capacity for SOP
Plenty of source with chirp
Combination with FDM and/or CDM
Additional link margins
Low peak-to-average ratio.
Robustness against interference and multipath
Excellent correlation characteristics
Potential high precision ranging.
An selectivity for FFD and RFD
Chirp vs. Non chirp
Li, Takizawa, Sasaki, Hara, Itami, Ikegami, Kohno, NICT