An Energy-Efficient Triple-Channel UWB-based Cognitive Radio
An Energy-Efficient Triple-Channel UWB-based Cognitive RadioByNam-Seog KimA dissertation submitted in partial satisfaction of theRequirements for the degree ofDoctor of PhilosophyinEngineering – Electrical Engineering and Computer Sciencesin theGRADUATE DIVISIONof theUNIVERSITY of CALIFORNIA, BERKELEYCommittee in charge:Professor Jan Rabaey, ChairProfessor Ali M. NiknejadProfessor Paul K. WrightSpring 2014
An Energy-Efficient Triple-Channel UWB-based Cognitive RadioCopyright 2014byNam-Seog Kim
An Energy-Efficient Triple-Channel UWB-based Cognitive RadiobyNam-Seog KimDoctor of Philosophy in Electrical Engineering and Computer ScienceUniversity of California, BerkeleyProfessor Jan M. Rabaey, ChairThe proposed triple-channel UWB-based cognitive radio exploits spectral crowding andcoexistence of other wireless devices as the number of sensors and wearable computingdevices increases in 3.1GHz to 10.6GHz ISM band to achieve energy efficient 1Gb/s shortrange wireless communication. A dual-resolution analog wavelet-based spectrum performsbandwidth-and frequency-agile band pass filter (BPF) to detect narrowband and widebandinterferers with low power consumption. A charge-pump-based triangular waveformgenerators and a source follower type low pass filter (LPF) generates basis function for thespectrum sensing with 132MHz sensing resolution. A Low power integer-N QPLL withreduced reference spur by digital calibration on mismatch of the charge pump currentsupports the tuning frequencies with a linear tuned wide range two stage ring-VCO and alow power programmable true-single-phase-clock (TSPC) divider. The proposed Triplechannel UWB-based cognitive radio was fabricated in 1V 65nm CMOS GP process. Thetest chip size is 2.3 2 mm2, and the active area is 2.1mm2. The data rate by using triangularshaped BPSK data is 1Gb/s at 1m communication. The lowest FoM of the energy/bit is61pJ/bit, and the highest FoM is 102pJ/bit. It achieves BER from 9.2 10-7 to 1.1 10-4according to frequency allocation of the triple-channels. The triple-channel UWB-basedcognitive radio can provide energy efficient high-data rate wireless communication evenwith over 20% channel occupation.
Dedicated to my Family i
ContentsList of Figures vList of Tables ix1 Introduction11.1 High-Data-Rate and Short-Range-Radio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 Comparison between UWB Radio and 60GHz Radio . . . . . . . . . . . . . . . . . . . . 41.3 Interferers in UWB band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.4 UWB-based Cognitive Radios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81.5 Dissertation Outline. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Multi-Channel High-Data-Rate UWB-based Cognitive Radio2.1 Modulation Schemes of the UWB Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . .11112.2 Pulse Shaping of the UWB Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112.3 Single-Channel UWB-based Cognitive Radio . . . . . . . . . . . . . . . . . . . . . . . . 132.4 Multi-Channel UWB-based Cognitive Radio . . . . . . . . . . . . . . . . . . . . . . . . . 162.5 Adaptive BW Multi-Channel UWB-based Cognitive Radio . . . . . . . . . . . . . . 202.6 Link Budget for Triple Channel UWB-based Cognitive Radio . . . . . . . . . . . . 222.7 Group Delay of Multi-Channel UWB-based Cognitive Radio . . . . . . . . . . . . 263 Dual-Resolution Analog Wavelet-based Wideband Spectrum Sensing 273.1 Spectrum Sensing in UWB band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273.2 Wideband Spectrum Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283.3 An Analog Wavelet-based Wideband Spectrum Sensing . . . . . . . . . . . . . . . . 303.4 Spectrum Sensing Resolution for a UWB-based Cognitive Radios . . . . . . . . . 36ii
3.5 Triangular waveform generation with Source Follower LPF for Side-lobeReduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383.5.1 Triangular waveform generation with Source Follower LPF for Side-lobeReduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383.5.2 A Low power Triangular Waveform Generator . . . . . . . . . . . . . . . . . . 393.5.3 Side-lobe Reduction of Triangular Waveform . . . . . . . . . . . . . . . . . . . 423.5.4 Modified Source-Follower-based Butterworth LPF . . . . . . . . . . . . . . . 433.5.5 Proposed Composite Triangular Waveform Generator with LPF . . . . 453.6 Dual-Resolution Spectrum Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463.7 Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493.8 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 A 3-11GHz Low-Power Integer-N QPLL534.1 Wideband QPLL for UWB-based Cognitive Radio . . . . . . . . . . . . . . . . . . . . . . 534.2 Two-stage Linear Tuning Differential QVCO . . . . . . . . . . . . . . . . . . . . . . . . . . . 544.3 Digital Calibration for Charge Pump Mismatch . . . . . . . . . . . . . . . . . . . . . . . . . 574.4 A Wideband Low-Power TSPC Frequency Divider . . . . . . . . . . . . . . . . . . . . . . 614.4.1 Truly Modular Programmable Divider . . . . . . . . . . . . . . . . . . . . . . . . . 634.4.2 N/P-TSPC Latches with Gated Inverting Keeper . . . . . . . . . . . . . . . . . 634.5 Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 684.5.1 A 3-11GHz Low-Power Integer-N QPLL with Spur ReductionTechnique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 684.5.2 A 0.02-6.5GHz Low-Power TSPC Programmable FrequencyDivider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 714.6 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 755 Triple Channel UWB-based Cognitive IR-UWB765.1 A Carrier-based UWB Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76iii
5.2 A Triple-Channel UWB-based Cognitive Radio . . . . . . . . . . . . . . . . . . . . . . . . . 775.3 Transmitter of the triple-channel UWB-based Cognitive Radio . . . . . . . . . . . . . . 795.3.1 Triangular-shaped BPSK modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 795.3.2 Up-Conversion Mixer and Modulation Multiplier . . . . . . . . . . . . . . . . . 805.3.3 Differential to Single-ended convertor and Antenna Driver . . . . . . . . . . 825.4 Receiver of the triple-channel UWB-based Cognitive Radio . . . . . . . . . . . . . . . . 835.4.1 Quadrature Analog Correlation Receiver . . . . . . . . . . . . . . . . . . . . . . . . 825.4.2 Wideband Low Noise Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 865.4.3 Down-Conversion Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 885.4.4 Analog Correlation Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 895.4.5 Variable Gain Amplifier with DCOC . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.5 UWB Chip Antenna 3.1 -10.3 GHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 945.6 Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 955.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1066 Conclusion1076.1 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1076.2 Contribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1096.3 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111Bibliographyiv
List of Figures1.1 Ubiquitous wireless systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 UWB spectrum mask as defined by FCC and various type of UWB radios . . . . . . . . . . 21.3 Worldwide spectrum availability at the 60 GHz band and Atmospheric propagationattenuation versus frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.4 UWB and 60GHz transceivers FoM (Energy/bit) relative to data rate and process . . . . 51.5 Required data rate with the resolution of the screen for uncompressed wireless datacommunication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.6 Services licensed to operate in the UWB band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72.1 Time domain pulse shapes modulated with 1000 random bit sequence and power spectraldensity of the (a) square, (b) triangle, (c) cosine, (d) Gaussian, and (d) Hann for 1Gb/sdata rate. The null-to-null bandwidth (BW) for 1Gb/s and the carrier amplitude (A) to get-41dBM/MHz spectral density are included . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.2 (a) An example of the interferers with 30% channel occupation in MATLAB simulation(The carrier frequency is randomly decided with 10MHz resolution from 3.1GHz to10.6GHz) and (b) a single-channel 1Gb/s UWB-based CR with triangular BPSKpulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142.3 (a) An example of the interferers with 30% channel occupation in MATLAB simulation(The carrier frequency is randomly decided with 10MHz resolution from 3.1GHz to10.6GHz) and (b) a single-channel 1Gb/s UWB-based CR with triangular BPSKpulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142.4 (a) Free path loss and (b) the SNR at the receiver with center frequency . . . . . . . . . . . . 162.5 An example of the interferers with 30% channel occupation in MATLAB simulation (Thecarrier frequency is randomly decided with 10MHz resolution from 3.1GHz to 10.6GHz)and with a triple-channel 1Gb/s UWB-based CR with triangular BPSK pulses . . . . . . . 172.6 EPUB with the number of sub-channels in multi-channel UWB-based CR for 1Gb/s datarate with 30% spectrum utilization environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182.7 Performance comparison between a single-channel and a triple-channel UWB-based CRsin terms of EPUB except communication fail cases of the single-channel CR along withchannel occupancy rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19v
2.8 An example of the interferers with 30% channel occupation in MATLAB simulation (Thecarrier frequency is randomly decided with 10MHz resolution from 3.1GHz to 10.6GHz)with a triple-channel 1Gb/s UWB-based CR with triangular BPSK pulses and adaptiveBW for respective sub-channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202.9 Comparison between constant BW and adaptive BW of the triple-channel CR in terms ofEPUB with channel resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212.10 (a) Receiver sensitivity and (b) required noise factor of the receiver chain of the singlechannel UWB-based CR with different carrier frequency and communication distance. 253.1 Block diagrams for Nyquist wideband sensing algorithms of (a) multiband joint detection,(b) wavelet detection, (c) sweep-tune detection, and (d) filter-band detection . . . . . . . . 303.2 Block diagrams for sub-Nyquist wideband sensing algorithms of (a) analog-toinformation converter based wideband sensing, (b) modulated wideband converter-basedwideband sensing, (c) multi-coset sampling-based wideband sensing, and (d) multi-ratesub-Nyquist sampling-based wideband sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323.3 Functional block diagram of the analog wavelet-based spectrum sensing . . . . . . . . . . . 353.4 (a) Statistical Analysis in terms of the spectrum utilization efficiency and the sensingtime, and (b) the quantized spectrum sensing resolution and maximum and minimumcarrier frequency of the PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373.5 Functional block diagram of the modified analog wavelet-based spectrum sensing . . . 383.6 (a) Time domain plot and (b) power spectral densities of triangular, Gaussian, and Hannwaveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393.7 (a) Proposed fully differential Charge pump based triangular waveform generator, (b) a50% duty cycle correction circuit, and (c) simulated output waveforms of the triangularwaveform generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413.8 (a) Time domain plot and (b) power spectral densities of the triangular waveform withoutLPF and with 4th order Butterworth LPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433.9 Modified source-follower-based 4th order Butterworth LPF . . . . . . . . . . . . . . . . . . . . . 443.10 Proposed composite triangular waveform generator with LPF and (b) its outputwaveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453.11 Methods to make brick wall BPF with (a) one carrier with a high-order LPF, (b) multicarriers with a low-order narrow-BW LPF, and (c) Triple carrier with a tunable dualresolution LPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46vi
3.12 Proposed dual-resolution analog wavelet-based spectrum sensing . . . . . . . . . . . . . . . . 483.13 (a) time-domain wavelet and (b) spectrogram for MOD0 and (c) time-domain waveletand (d) spectrogram for MOD1 of the proposed triangular waveform generator withLPF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503.14 Dual-resolution analog wavelet-based spectrum sensing for narrow band interferer (a, b)at the center of the channel and (c, d) at the boundary of the channel . . . . . . . . . . . . . . 513.15 Dual-resolution analog wavelet-based spectrum sensing for wideband interferer . . . . 524.1 Reference spur issue in wavelet-based spectrum sensing . . . . . . . . . . . . . . . . . . . . . . . . 534.2 (a) The proposed supply regulated two stage differential QVCO, and (b) the QVCO unitcell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554.3 (a) The conventional dioded connected PMOS load error amplifier, (b) the proposed erroramplifier with enhanced gm technique, and comparion in terms of (c) gain, (d) 3dB BW,and (e) power consumption with input common mode level(VCM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564.4 The proposed QPLL Architecture with digital calibration for CP . . . . . . . . . . . . . . . . . 574.5 The proposed charge pump with the replica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594.5 The proposed charge pump with the replica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594.6 The proposed digital calibration for the CP current mismatch . . . . . . . . . . . . . . . . . . . . 604.7 Principal operation of the digital cariblation for Iup Idn case . . . . . . . . . . . . . . . . . . . 604.8 Intrinsic delay and sub-threshold source drain leakage current of the NMOS withtechnology scaling (ITRS2003) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624.9 (a) Fully modular PDIV with extended division range architecture and (b) modified 2/3divider cell for TSPC latches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644.10 (a) N-TSPC and (b) P-TSPC latches with the gated inverter for leakage compensation atdynamic nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644.11 (a) Prescaler logic and (b) end-of-cycle logic with N/P-TSPC latches of the modified2/3-divider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 664.12 Simulated leakage effect on the dynamic nodes of the prescaler P-TSPC latch withoutcompensation technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67vii
4.13 Simulated (a) minimum and (b) maximum operating frequencies with the strength ratioof the keeper to the driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674.14 (a) Chip photo of the proposed QPLL and (b) Measured VCO output tuning range withan 8 divider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 684.15 Comparison of the measured QPLL output spectrum and phase noise (a,c) without and(b,d) with the digital calibration technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 694.16 (a) Layout of the proposed TSPC PDIV with the gated inverting keeper and (b) chipphoto of the test chip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 724.17 TSPC PDIV output of the non-gate inverting keeper with (a) 80-division (20MHz) and(b) 24-division ratio (20MHz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 724.18 TSPC PDIV output of the gate inverting keeper with (a) 80-division (6.5GHz), (b) 24division (6.5GHz), (c) 80-division (20MHz), and (d) 24-division ratio(20MHz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .734.19 (a) Power consumption of the PDIV and (b) phase noise with 6.5GHz inputfrequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 745.1 Architecture of Triple Channel UWB-based Cognitive IR-UWB . . . . . . . . . . . . . . . . . . 785.2 (a) Block diagram and (b) waveforms of the triangular-shaped BPSK modulation . . . . 805.3 Up-conversion mixer and modulation multiplier for the triangular-shaped BPSKmodulated signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 815.4 Differential to single-ended converter and antenna driver with BPF . . . . . . . . . . . . . . . .825.5 (a) Direct conversion (DC), (b) transmitted reference (TR), and (c) quadrature analogcorrelation (QAC) receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855.6 An ultra-wideband amplifier using Chebyshev active filter . . . . . . . . . . . . . . . . . . . . . . 865.7 Gilbert-type double balanced active mixer with resistive source degeneration . . . . . . . 895.8 Gilbert-type Analog correlation circuit with a multiplier and integrator . . . . . . . . . . . . . 905.9 (a) Variable gain amplifier (VGA), (b) simulated gain curve with differential controlvoltage, and (c) VGA with DC offset cancellation and the control . . . . . . . . . . . . . . . . . 925.10 (a) Antenna board wi
An Energy-Efficient Triple-Channel UWB-based Cognitive Radio . By . Nam-Seog Kim . . bandwidth-and frequency-agile band pass filter (BPF) to detect narrowband and wideband interferers with low power consumption. A charge-pump-based triangular waveform . 5.3.3 Differential to Single-ended convertor and Antenna Driver . . . . . . . . . . 82
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