In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cip... more In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cipher CIKS-1 against linear crypt-analysis(LC). A feature of the CIKS-1 is the use of both Data-Dependent permutations(DDP) and internal key scheduing which consist in data-dapendent transformation of the round subkeys. Taking into account the structure of CIKS-1 we investigate linear approximation. That is, we consider 16 linear approximations with p = 3/4 for 16 parallel modulo 22 additions to construct one-round linear approximation and derive one-round linear approximation with the probability of P = 1/2 + 2-17 by Piling-Up lemma. Also we estimate that the P is a valid probability of one-round approximation and achieve that the probability P for one-round approximation is better than 1/2 + 2-17 through experiments. Then we construct 3-round linear approximation with P = 1/2 +2-17 using this one-round approximation and can attack the reduced 5-round CIKS-1 with 64-bit block by LC. In conclusion, we present that our attack requires about 236 chosen plaintexts with a probability of success of 78.5% and 1/5 × 232 × 236 ≈ 265.7 encryption times to recover last round(5-round) key. In addition, we discuss a few improvements of the cipher CIKS-1.
This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we ... more This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we will show how to construct a 16-round distinguisher which distinguishes 16 rounds of Skipjack from a random permutation. The distinguisher is used to attack on 18(5∼22) and 23(5∼27) rounds of Skipjack. We can also construct a 20-round distinguisher based on the 16-round distinguisher. This distinguisher is used to attack on 22(1∼22) and 27(1∼27) rounds of Skipjack. The 80bit user key of 27 rounds of Skipjack can be recovered with 2 50 chosen plaintexts and 3 · 2 75 encryption times.
In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cip... more In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cipher CIKS-1 against linear crypt-analysis(LC). A feature of the CIKS-1 is the use of both Data-Dependent permutations(DDP) and internal key scheduing which consist in data-dapendent transformation of the round subkeys. Taking into account the structure of CIKS-1 we investigate linear approximation. That is, we consider 16 linear approximations with p = 3/4 for 16 parallel modulo 22 additions to construct one-round linear approximation and derive one-round linear approximation with the probability of P = 1/2 + 2-17 by Piling-Up lemma. Also we estimate that the P is a valid probability of one-round approximation and achieve that the probability P for one-round approximation is better than 1/2 + 2-17 through experiments. Then we construct 3-round linear approximation with P = 1/2 +2-17 using this one-round approximation and can attack the reduced 5-round CIKS-1 with 64-bit block by LC. In conclusion, we present that our attack requires about 236 chosen plaintexts with a probability of success of 78.5% and 1/5 × 232 × 236 ≈ 265.7 encryption times to recover last round(5-round) key. In addition, we discuss a few improvements of the cipher CIKS-1.
This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we ... more This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we will show how to construct a 16-round distinguisher which distinguishes 16 rounds of Skipjack from a random permutation. The distinguisher is used to attack on 18(5∼22) and 23(5∼27) rounds of Skipjack. We can also construct a 20-round distinguisher based on the 16-round distinguisher. This distinguisher is used to attack on 22(1∼22) and 27(1∼27) rounds of Skipjack. The 80bit user key of 27 rounds of Skipjack can be recovered with 2 50 chosen plaintexts and 3 · 2 75 encryption times.
IEEE Transactions on Computer-aided Design of Integrated Circuits and Systems, 2007
A numerical approach to simulate the intrinsic noise sources within transistors is described, and... more A numerical approach to simulate the intrinsic noise sources within transistors is described, and the impact of spatial correlation between local fluctuations is investigated. Using a 2-D numerical device solver, spectral densities for the gate and drain noise current sources and their correlation are evaluated using a Green's function approach, which is an equivalent of Shockley's impedance field method. Case studies with an AlGaN/GaN high electron mobility transistor are supported by measurement data. Using a spatial noise source correlation model, similar terminal noise is found to the case of an uncorrelated diffusion noise source. Therefore, using uncorrelated local noise sources to calculate the intrinsic terminal noise is found to be valid even for the submicrometer gate length field-effect transistor studied.
A scalable device model for high-power, large periphery AlGaN-GaN HEMTs on SiC has been developed... more A scalable device model for high-power, large periphery AlGaN-GaN HEMTs on SiC has been developed which includes device self-heating. The parameterized model coefficients were evaluated using S-parameters obtained from isothermal bias contours and pulsed I-V measurements. Model scaling with device size was examined by comparing with measurements for peripheries from 0.25 mm to 1.5 mm. The scaled model showed good agreement with measured S-parameters and power sweep data.
... Frequency (GHz) Fig. G. Coiriparisori or rrieasirred arid sirriirlirl,etl S-parameters for a ... more ... Frequency (GHz) Fig. G. Coiriparisori or rrieasirred arid sirriirlirl,etl S-parameters for a four-stage single-gate NDA. Input Power (dam) ... [io] OY.4i$acher, J. s11wi., JR mealy, N. G. eimwu: K. Chu, M. Murphy, W. J. Schaff, L. F. Eastman, R. Dimitrov, L. Wittmer, M. Stutzmann: CV. ...
IEEE Transactions on Microwave Theory and Techniques, 2005
A nonlinear field-effect transistor equivalent-circuit model is examined to identify the fundamen... more A nonlinear field-effect transistor equivalent-circuit model is examined to identify the fundamental mechanisms that up-convert baseband 1 noise to near-carrier sideband noise when the device is operated in the large-signal regime. This model captures all physical noise sources and nonlinearities in the transistor, and thereby allows a general cause-and-effect treatment. The noise sources in the equivalent-circuit model are determined using low-frequency spectrum analyzer and microwave noise-figure meter data. Using the example of an AlGaN/GaN high electron-mobility transistor, the developed model correctly describes both the measured near-carrier sideband amplitude and phase noise simultaneously.
ABSTRACT A numerical approach to simulate the intrinsic noise sources within transistors is descr... more ABSTRACT A numerical approach to simulate the intrinsic noise sources within transistors is described. Using a 2D numerical device solver, spectral densities for the gate and drain noise current sources and their correlation are evaluated using a Green's function approach, an equivalent of Shockley's impedance field method. Case studies with AlGaN/GaN HEMTs compare the numerical simulation results to those from measurements, showing good agreement.
... BM Green, K. Chu, and LF Eastman are with the School of Electrical Engineering, Cornell Unive... more ... BM Green, K. Chu, and LF Eastman are with the School of Electrical Engineering, Cornell University, Ithaca, NY 14853 USA. ... Publisher Item Identifier S 1051-8207( 00)07177-4. Fig. 1. Circuit schematic for the fabricated NDA. ...
Transistor nonlinearities are examined to assess their effects on intrinsic noise properties. The... more Transistor nonlinearities are examined to assess their effects on intrinsic noise properties. The noise sources in a nonlinear equivalent-circuit model are determined using low frequency spectrum analyzer and microwave noise figure meter data, while the other circuit elements are determined using bias-dependent scattering parameter measurements and analytic nonlinear parameter expressions. This model identifies the intrinsic noise mechanisms, and allows the investigation of their influence on extrinsic noise when the device is operated in either linear of the nonlinear regime. Using the example of AlGaN/GaN high electron mobility transistor, the model correctly predicts the near-carrier sideband amplitude and phase noise simultaneously.
IEEE Transactions on Microwave Theory and Techniques, 2003
Intrinsic noise sources and their correlation in gallium-nitride high electron-mobility transisto... more Intrinsic noise sources and their correlation in gallium-nitride high electron-mobility transistors are extracted and studied. Microwave noise measurements have been performed over the frequency range of 0.8-5.8 GHz. Using measured noise and scattering parameter data, the gate and drain noise sources and their correlation are determined using an equivalent-circuit representation. This model correctly predicts the frequency-dependent noise for two devices having different gate length. Three noise mechanisms are identified in these devices, namely, those due to velocity fluctuation, gate leakage, and traps.
AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-mic... more AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-microwave integrated-cir-cuit (MMIC) amplifiers with high gain and power-added efficiency (PAE) have been fabricated on high-thermal conductivity SiC substrates. A ...
Intrinsic noise sources and their correlation in AlGaN/GaN HEMTs are extracted and studied. Using... more Intrinsic noise sources and their correlation in AlGaN/GaN HEMTs are extracted and studied. Using three noise parameters obtained from microwave noise measurements and S-parameter data, two intrinsic noise sources and their correlation are specified by applying a noise deembedding technique, and their dependence on frequency and bias point is investigated.
We report the first demonstration of Class B push-pull operation of AlGaN/GaN HEMTs on SiC substr... more We report the first demonstration of Class B push-pull operation of AlGaN/GaN HEMTs on SiC substrates, thereby taking advantage of lower thermal dissipation while achieving linear operation and allowing higher power density in large-area devices. This lower thermal dissipation can be achieved because of the potentially higher power-added-efficiency (PAE) of Class B operation, relative to Class A operation
IEEE Transactions on Microwave Theory and Techniques, 2001
AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-mic... more AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-microwave integrated-cir-cuit (MMIC) amplifiers with high gain and power-added efficiency (PAE) have been fabricated on high-thermal conductivity SiC substrates. A ...
In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cip... more In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cipher CIKS-1 against linear crypt-analysis(LC). A feature of the CIKS-1 is the use of both Data-Dependent permutations(DDP) and internal key scheduing which consist in data-dapendent transformation of the round subkeys. Taking into account the structure of CIKS-1 we investigate linear approximation. That is, we consider 16 linear approximations with p = 3/4 for 16 parallel modulo 22 additions to construct one-round linear approximation and derive one-round linear approximation with the probability of P = 1/2 + 2-17 by Piling-Up lemma. Also we estimate that the P is a valid probability of one-round approximation and achieve that the probability P for one-round approximation is better than 1/2 + 2-17 through experiments. Then we construct 3-round linear approximation with P = 1/2 +2-17 using this one-round approximation and can attack the reduced 5-round CIKS-1 with 64-bit block by LC. In conclusion, we present that our attack requires about 236 chosen plaintexts with a probability of success of 78.5% and 1/5 × 232 × 236 ≈ 265.7 encryption times to recover last round(5-round) key. In addition, we discuss a few improvements of the cipher CIKS-1.
This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we ... more This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we will show how to construct a 16-round distinguisher which distinguishes 16 rounds of Skipjack from a random permutation. The distinguisher is used to attack on 18(5∼22) and 23(5∼27) rounds of Skipjack. We can also construct a 20-round distinguisher based on the 16-round distinguisher. This distinguisher is used to attack on 22(1∼22) and 27(1∼27) rounds of Skipjack. The 80bit user key of 27 rounds of Skipjack can be recovered with 2 50 chosen plaintexts and 3 · 2 75 encryption times.
In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cip... more In this paper, we firstly evaluate the resistance of the reduced 5-round version of the block cipher CIKS-1 against linear crypt-analysis(LC). A feature of the CIKS-1 is the use of both Data-Dependent permutations(DDP) and internal key scheduing which consist in data-dapendent transformation of the round subkeys. Taking into account the structure of CIKS-1 we investigate linear approximation. That is, we consider 16 linear approximations with p = 3/4 for 16 parallel modulo 22 additions to construct one-round linear approximation and derive one-round linear approximation with the probability of P = 1/2 + 2-17 by Piling-Up lemma. Also we estimate that the P is a valid probability of one-round approximation and achieve that the probability P for one-round approximation is better than 1/2 + 2-17 through experiments. Then we construct 3-round linear approximation with P = 1/2 +2-17 using this one-round approximation and can attack the reduced 5-round CIKS-1 with 64-bit block by LC. In conclusion, we present that our attack requires about 236 chosen plaintexts with a probability of success of 78.5% and 1/5 × 232 × 236 ≈ 265.7 encryption times to recover last round(5-round) key. In addition, we discuss a few improvements of the cipher CIKS-1.
This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we ... more This paper describes saturation attacks on reduced-round versions of Skipjack. To begin with, we will show how to construct a 16-round distinguisher which distinguishes 16 rounds of Skipjack from a random permutation. The distinguisher is used to attack on 18(5∼22) and 23(5∼27) rounds of Skipjack. We can also construct a 20-round distinguisher based on the 16-round distinguisher. This distinguisher is used to attack on 22(1∼22) and 27(1∼27) rounds of Skipjack. The 80bit user key of 27 rounds of Skipjack can be recovered with 2 50 chosen plaintexts and 3 · 2 75 encryption times.
IEEE Transactions on Computer-aided Design of Integrated Circuits and Systems, 2007
A numerical approach to simulate the intrinsic noise sources within transistors is described, and... more A numerical approach to simulate the intrinsic noise sources within transistors is described, and the impact of spatial correlation between local fluctuations is investigated. Using a 2-D numerical device solver, spectral densities for the gate and drain noise current sources and their correlation are evaluated using a Green's function approach, which is an equivalent of Shockley's impedance field method. Case studies with an AlGaN/GaN high electron mobility transistor are supported by measurement data. Using a spatial noise source correlation model, similar terminal noise is found to the case of an uncorrelated diffusion noise source. Therefore, using uncorrelated local noise sources to calculate the intrinsic terminal noise is found to be valid even for the submicrometer gate length field-effect transistor studied.
A scalable device model for high-power, large periphery AlGaN-GaN HEMTs on SiC has been developed... more A scalable device model for high-power, large periphery AlGaN-GaN HEMTs on SiC has been developed which includes device self-heating. The parameterized model coefficients were evaluated using S-parameters obtained from isothermal bias contours and pulsed I-V measurements. Model scaling with device size was examined by comparing with measurements for peripheries from 0.25 mm to 1.5 mm. The scaled model showed good agreement with measured S-parameters and power sweep data.
... Frequency (GHz) Fig. G. Coiriparisori or rrieasirred arid sirriirlirl,etl S-parameters for a ... more ... Frequency (GHz) Fig. G. Coiriparisori or rrieasirred arid sirriirlirl,etl S-parameters for a four-stage single-gate NDA. Input Power (dam) ... [io] OY.4i$acher, J. s11wi., JR mealy, N. G. eimwu: K. Chu, M. Murphy, W. J. Schaff, L. F. Eastman, R. Dimitrov, L. Wittmer, M. Stutzmann: CV. ...
IEEE Transactions on Microwave Theory and Techniques, 2005
A nonlinear field-effect transistor equivalent-circuit model is examined to identify the fundamen... more A nonlinear field-effect transistor equivalent-circuit model is examined to identify the fundamental mechanisms that up-convert baseband 1 noise to near-carrier sideband noise when the device is operated in the large-signal regime. This model captures all physical noise sources and nonlinearities in the transistor, and thereby allows a general cause-and-effect treatment. The noise sources in the equivalent-circuit model are determined using low-frequency spectrum analyzer and microwave noise-figure meter data. Using the example of an AlGaN/GaN high electron-mobility transistor, the developed model correctly describes both the measured near-carrier sideband amplitude and phase noise simultaneously.
ABSTRACT A numerical approach to simulate the intrinsic noise sources within transistors is descr... more ABSTRACT A numerical approach to simulate the intrinsic noise sources within transistors is described. Using a 2D numerical device solver, spectral densities for the gate and drain noise current sources and their correlation are evaluated using a Green's function approach, an equivalent of Shockley's impedance field method. Case studies with AlGaN/GaN HEMTs compare the numerical simulation results to those from measurements, showing good agreement.
... BM Green, K. Chu, and LF Eastman are with the School of Electrical Engineering, Cornell Unive... more ... BM Green, K. Chu, and LF Eastman are with the School of Electrical Engineering, Cornell University, Ithaca, NY 14853 USA. ... Publisher Item Identifier S 1051-8207( 00)07177-4. Fig. 1. Circuit schematic for the fabricated NDA. ...
Transistor nonlinearities are examined to assess their effects on intrinsic noise properties. The... more Transistor nonlinearities are examined to assess their effects on intrinsic noise properties. The noise sources in a nonlinear equivalent-circuit model are determined using low frequency spectrum analyzer and microwave noise figure meter data, while the other circuit elements are determined using bias-dependent scattering parameter measurements and analytic nonlinear parameter expressions. This model identifies the intrinsic noise mechanisms, and allows the investigation of their influence on extrinsic noise when the device is operated in either linear of the nonlinear regime. Using the example of AlGaN/GaN high electron mobility transistor, the model correctly predicts the near-carrier sideband amplitude and phase noise simultaneously.
IEEE Transactions on Microwave Theory and Techniques, 2003
Intrinsic noise sources and their correlation in gallium-nitride high electron-mobility transisto... more Intrinsic noise sources and their correlation in gallium-nitride high electron-mobility transistors are extracted and studied. Microwave noise measurements have been performed over the frequency range of 0.8-5.8 GHz. Using measured noise and scattering parameter data, the gate and drain noise sources and their correlation are determined using an equivalent-circuit representation. This model correctly predicts the frequency-dependent noise for two devices having different gate length. Three noise mechanisms are identified in these devices, namely, those due to velocity fluctuation, gate leakage, and traps.
AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-mic... more AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-microwave integrated-cir-cuit (MMIC) amplifiers with high gain and power-added efficiency (PAE) have been fabricated on high-thermal conductivity SiC substrates. A ...
Intrinsic noise sources and their correlation in AlGaN/GaN HEMTs are extracted and studied. Using... more Intrinsic noise sources and their correlation in AlGaN/GaN HEMTs are extracted and studied. Using three noise parameters obtained from microwave noise measurements and S-parameter data, two intrinsic noise sources and their correlation are specified by applying a noise deembedding technique, and their dependence on frequency and bias point is investigated.
We report the first demonstration of Class B push-pull operation of AlGaN/GaN HEMTs on SiC substr... more We report the first demonstration of Class B push-pull operation of AlGaN/GaN HEMTs on SiC substrates, thereby taking advantage of lower thermal dissipation while achieving linear operation and allowing higher power density in large-area devices. This lower thermal dissipation can be achieved because of the potentially higher power-added-efficiency (PAE) of Class B operation, relative to Class A operation
IEEE Transactions on Microwave Theory and Techniques, 2001
AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-mic... more AbstractBroad-band high-power cascode AlGaN/GaN high electron-mobility transistor monolithic-microwave integrated-cir-cuit (MMIC) amplifiers with high gain and power-added efficiency (PAE) have been fabricated on high-thermal conductivity SiC substrates. A ...
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