Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873581
N. Areed
The development of communication engineering with integration technology demands size reduction of low frequency antennas as an important design perspective. In this work, a microstrip patch antenna with a c-shaped-slot implemented on a relatively thin substrate (about 0.03 λ0), and (εr = 2.2) is shown to bring a size reduction an ordinary microstrip patch antenna for the same resonant frequency. However size reduction comes at the cost of bandwidth and the gain which are then enhanced to a good level by using one pair of transmission-lines-feed and annular ring slots. The composite effect of integrating these techniques offers a low profile, broadband, and multi-band functionality. The proposed antenna is designed to function in the WIMAX (3.27–3.4GHz and 6.9–7.8GHz) bands and it is shown to bring a size reduction of about 40% compared to an ordinary microstrip patch antenna for the same resonant frequency.
{"title":"Low profile dual band slotted-patch antenna for WIMAX applications","authors":"N. Areed","doi":"10.1109/NRSC.2011.5873581","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873581","url":null,"abstract":"The development of communication engineering with integration technology demands size reduction of low frequency antennas as an important design perspective. In this work, a microstrip patch antenna with a c-shaped-slot implemented on a relatively thin substrate (about 0.03 λ0), and (εr = 2.2) is shown to bring a size reduction an ordinary microstrip patch antenna for the same resonant frequency. However size reduction comes at the cost of bandwidth and the gain which are then enhanced to a good level by using one pair of transmission-lines-feed and annular ring slots. The composite effect of integrating these techniques offers a low profile, broadband, and multi-band functionality. The proposed antenna is designed to function in the WIMAX (3.27–3.4GHz and 6.9–7.8GHz) bands and it is shown to bring a size reduction of about 40% compared to an ordinary microstrip patch antenna for the same resonant frequency.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"52 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116837622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873611
S. El-Khamy, H. Elsayed, M. Rizk
Automatic Digital signal type classification (ADSTC) has many important applications in both of the civilian and military domains. Most of the proposed classifiers can only recognize a few types of digital signals. This paper presents a novel technique that deals with the classification of multi-user chirp modulation signals. In this technique, a combination of higher order moments and higher order cumulants (up to eighth) are proposed as the effective features and different types of classifiers are used. Simulation results show that the proposed technique is able to classify the different types of chirp signals in additive white Gaussian noise (AWGN) channels with high accuracy and the neural network classifier (NN) outperforms other classifiers, namely, maximum likelihood classifier (ML), k nearest neighbor classifier (KNN), support vector machine classifier (SVM).
{"title":"Classification of multi-user chirp modulation signals using higher order cumulant features and four types of classifiers","authors":"S. El-Khamy, H. Elsayed, M. Rizk","doi":"10.1109/NRSC.2011.5873611","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873611","url":null,"abstract":"Automatic Digital signal type classification (ADSTC) has many important applications in both of the civilian and military domains. Most of the proposed classifiers can only recognize a few types of digital signals. This paper presents a novel technique that deals with the classification of multi-user chirp modulation signals. In this technique, a combination of higher order moments and higher order cumulants (up to eighth) are proposed as the effective features and different types of classifiers are used. Simulation results show that the proposed technique is able to classify the different types of chirp signals in additive white Gaussian noise (AWGN) channels with high accuracy and the neural network classifier (NN) outperforms other classifiers, namely, maximum likelihood classifier (ML), k nearest neighbor classifier (KNN), support vector machine classifier (SVM).","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116863914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873642
M. Hassan, A. Youssef, Y. Kadah
Ultrasound imaging is an efficient, noninvasive, method for medical diagnosis. Efficient implementations of digital ultrasound systems on embedded digital signal processing on FPGA, this miniaturization enables a design with low power consumption, low noise, and light weight. This paper proposed embedded digital signal processing (DSP) for digital ultrasound imaging on FPGA (Xilinx, Inc.). The DSP was composed of FIR Hilbert transform filter, which was used to generate Quadrature component (Q) from the In-phase component (I) of the ultrasound data. The envelope (magnitude) of the received echo was computed. The implementation has been done in the Virtex-5 FPGA. The objective of this work is to build embedded DSP for ultrasound imaging system using the FIR Hilbert transform filter, which will be described in the methods. The system was consisted of: the pipeline adder block to reconstruct the focus ultrasound line, the bit modifier block to modify the bit of the signal to 16 bit, the FIR Hilbert filter block to obtain the quadrature components, the fractional delay filter (in-phase filter) to compensate the delay when we were used a high FIR order, and the envelope detection block to compute the envelope of the in-phase and quadrature components. The Hilbert filter is implemented in the form whereby the zero tap coefficients are not computed and therefore an order L filter uses only L/2 multiplications. This was reducing the computational time by a half. The simulation results of FIR Hilbert filter and the envelope detection are near to the ideal Hilbert. The results of the implementation are good compared to the simulation results. From the implementation result the total estimated power consumption equal to 0.8142W and the device utilization was acceptable. It is possible for the system to accept anther devices for further processing. The hardware architecture of the design provided flexibility.
{"title":"Embedded digital signal processing for digital ultrasound imaging","authors":"M. Hassan, A. Youssef, Y. Kadah","doi":"10.1109/NRSC.2011.5873642","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873642","url":null,"abstract":"Ultrasound imaging is an efficient, noninvasive, method for medical diagnosis. Efficient implementations of digital ultrasound systems on embedded digital signal processing on FPGA, this miniaturization enables a design with low power consumption, low noise, and light weight. This paper proposed embedded digital signal processing (DSP) for digital ultrasound imaging on FPGA (Xilinx, Inc.). The DSP was composed of FIR Hilbert transform filter, which was used to generate Quadrature component (Q) from the In-phase component (I) of the ultrasound data. The envelope (magnitude) of the received echo was computed. The implementation has been done in the Virtex-5 FPGA. The objective of this work is to build embedded DSP for ultrasound imaging system using the FIR Hilbert transform filter, which will be described in the methods. The system was consisted of: the pipeline adder block to reconstruct the focus ultrasound line, the bit modifier block to modify the bit of the signal to 16 bit, the FIR Hilbert filter block to obtain the quadrature components, the fractional delay filter (in-phase filter) to compensate the delay when we were used a high FIR order, and the envelope detection block to compute the envelope of the in-phase and quadrature components. The Hilbert filter is implemented in the form whereby the zero tap coefficients are not computed and therefore an order L filter uses only L/2 multiplications. This was reducing the computational time by a half. The simulation results of FIR Hilbert filter and the envelope detection are near to the ideal Hilbert. The results of the implementation are good compared to the simulation results. From the implementation result the total estimated power consumption equal to 0.8142W and the device utilization was acceptable. It is possible for the system to accept anther devices for further processing. The hardware architecture of the design provided flexibility.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129335837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873614
E. Hagras, Doaa El-Saied, Hazem H. Aly
In this paper, an efficient key management scheme based on public key elliptic curves signcryption (ECS) scheme for Wireless Sensor Networks (WSN) has been proposed. The proposed algorithm is compared with the scheme given in [1]. For 250 cluster node, the saving in the total number of operations, key storage requirements, energy consumptions, and communication overhead are 75%, 96%, 23.79 m Joule, and 40% respectively compared with [1]. The proposed protocol is efficient in terms of complexity, number of message exchange, computation, and storage requirements compared with [1]. The proposed key management possesses not only provided confidentiality, authentication, integrity but also unforgeability.
提出了一种基于公钥椭圆曲线签名加密(ECS)的无线传感器网络密钥管理方案。将该算法与[1]中给出的方案进行了比较。对于250个集群节点，与[1]相比，总操作次数、关键存储需求、能耗和通信开销分别节省75%、96%、23.79 m Joule和40%。与[1]相比，该协议在复杂度、消息交换数量、计算量和存储需求等方面都具有较高的效率。所提出的密钥管理方法不仅具有保密性、认证性、完整性，而且具有不可伪造性。
{"title":"Energy efficient key management scheme based on elliptic curve signcryption for Wireless Sensor Networks","authors":"E. Hagras, Doaa El-Saied, Hazem H. Aly","doi":"10.1109/NRSC.2011.5873614","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873614","url":null,"abstract":"In this paper, an efficient key management scheme based on public key elliptic curves signcryption (ECS) scheme for Wireless Sensor Networks (WSN) has been proposed. The proposed algorithm is compared with the scheme given in [1]. For 250 cluster node, the saving in the total number of operations, key storage requirements, energy consumptions, and communication overhead are 75%, 96%, 23.79 m Joule, and 40% respectively compared with [1]. The proposed protocol is efficient in terms of complexity, number of message exchange, computation, and storage requirements compared with [1]. The proposed key management possesses not only provided confidentiality, authentication, integrity but also unforgeability.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"373 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126171193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873604
N. Soliman, A. Shaalan, M. Fouad
In this paper a new scheme is proposed for progressive image transmission over coded Orthogonal Frequency Division Multiplexing (OFDM) system with Low Density Parity Check Coding (LDPC). Trigonometric transforms are used in this scheme for improving the performance of the OFDM systems and reducing the Peak-to-Average Power Ratio (PAPR) of OFDM signal. It improves the error resilience ability and transmission efficiency for progressive image transmission over Additive White Gaussian Noise (AWGN) channel. The Set Partitioning In Hierarchical Trees (SPIHT) algorithm is used for source coding of the images to be transmitted. In the proposed scheme the transmit data sequence of the OFDM signal after Inverse Fast Fourier Transform (IFFT) is grouped into in-phase and in-quadrature components, then each component is transformed using either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST). The simulation results show that adding the DST to the system improves the visual quality of reconstructed images and reduces the PAPR of OFDM signal more than the DCT.
{"title":"Robust image transmission with OFDM over an AWGN channel","authors":"N. Soliman, A. Shaalan, M. Fouad","doi":"10.1109/NRSC.2011.5873604","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873604","url":null,"abstract":"In this paper a new scheme is proposed for progressive image transmission over coded Orthogonal Frequency Division Multiplexing (OFDM) system with Low Density Parity Check Coding (LDPC). Trigonometric transforms are used in this scheme for improving the performance of the OFDM systems and reducing the Peak-to-Average Power Ratio (PAPR) of OFDM signal. It improves the error resilience ability and transmission efficiency for progressive image transmission over Additive White Gaussian Noise (AWGN) channel. The Set Partitioning In Hierarchical Trees (SPIHT) algorithm is used for source coding of the images to be transmitted. In the proposed scheme the transmit data sequence of the OFDM signal after Inverse Fast Fourier Transform (IFFT) is grouped into in-phase and in-quadrature components, then each component is transformed using either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST). The simulation results show that adding the DST to the system improves the visual quality of reconstructed images and reduces the PAPR of OFDM signal more than the DCT.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127635567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873634
M. Salah, A. Zekry, Mohammed Kamel
Filtering data in real-time requires dedicated hardware to meet demanding time requirements. If the statistics of the signal are not known, then adaptive filtering algorithms can be implemented to estimate the signals statistics iteratively. This paper aims to combine efficient filter structures with optimized code to create a system-on-chip (SOC) solution for various adaptive filtering problems specially unknown system identification. System identification is one of the most interesting applications for adaptive filters, especially for the Least Mean Square algorithm, due to its strength and calculus simplicity. Based on the error signal, the filter's coefficients are updated and becomes almost exactly as the unknown system' coefficients. Several different adaptive algorithms have been coded in VHDL as well as in MATLAB. The design is evaluated in terms of speed, hardware resources, and power consumption. System identification was mapped into a hardware description language, VHDL. The design was synthesized and implemented using FPGA (Xilinx Spartan3 3s200ft256 kit) with 50 MHz clock.
{"title":"FPGA implementation of LMS adaptive filter","authors":"M. Salah, A. Zekry, Mohammed Kamel","doi":"10.1109/NRSC.2011.5873634","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873634","url":null,"abstract":"Filtering data in real-time requires dedicated hardware to meet demanding time requirements. If the statistics of the signal are not known, then adaptive filtering algorithms can be implemented to estimate the signals statistics iteratively. This paper aims to combine efficient filter structures with optimized code to create a system-on-chip (SOC) solution for various adaptive filtering problems specially unknown system identification. System identification is one of the most interesting applications for adaptive filters, especially for the Least Mean Square algorithm, due to its strength and calculus simplicity. Based on the error signal, the filter's coefficients are updated and becomes almost exactly as the unknown system' coefficients. Several different adaptive algorithms have been coded in VHDL as well as in MATLAB. The design is evaluated in terms of speed, hardware resources, and power consumption. System identification was mapped into a hardware description language, VHDL. The design was synthesized and implemented using FPGA (Xilinx Spartan3 3s200ft256 kit) with 50 MHz clock.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114623690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873621
M. Fahmy, G. Raheem, U. S. Mohammed, O. Fahmy
Successful blind image deconvolution algorithms require the exact estimation of the Point Spread Function size, PSF. In the absence of any priori information about the imagery system and the true image, this estimation is normally done by trial and error experimentation, until an acceptable restored image quality is obtained. This paper, presents an exact estimation of the PSF size that yields the optimum restored image quality. The paper also describes a least squares PSF estimation, instead of the slow iterative update, that is commonly used in Iterative Blind Deconvolution software, IBD. Moreover, a technique is also proposed to improve the sharpness of the deconvolved images, by constrained maximization of the detail wavelet-coefficient entropies. Several simulations are given to verify these results.
{"title":"A Fast Iterative Blind image restoration algorithm","authors":"M. Fahmy, G. Raheem, U. S. Mohammed, O. Fahmy","doi":"10.1109/NRSC.2011.5873621","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873621","url":null,"abstract":"Successful blind image deconvolution algorithms require the exact estimation of the Point Spread Function size, PSF. In the absence of any priori information about the imagery system and the true image, this estimation is normally done by trial and error experimentation, until an acceptable restored image quality is obtained. This paper, presents an exact estimation of the PSF size that yields the optimum restored image quality. The paper also describes a least squares PSF estimation, instead of the slow iterative update, that is commonly used in Iterative Blind Deconvolution software, IBD. Moreover, a technique is also proposed to improve the sharpness of the deconvolved images, by constrained maximization of the detail wavelet-coefficient entropies. Several simulations are given to verify these results.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133233182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873600
M. El- Gendy, E. Sourour
Femtocells are a promising solution for the provision of high indoor coverage and capacity. Furthermore, OFDMA-based femtocells have proven to be highly versatile when dealing with cross-layer co-channel interference; however, concerns still exist related to the impact of the different access methods to femtocells in an overlaid network‥ Femtocells based on a Closed Subscribers group, where only device owners are allowed to connect, introduce severe interference to microcells' users. On the other hand, Open Access femtocells where any user can connect, does not bring many advantages to the femtocell owner [1]. In this paper, a study of the two types of access methods (Closed & Open Access) is proposed and a discussion of how to overcome their drawbacks by using the Hybrid access method is presented, which allows all users to connect but under restrictions. The performance of the model is evaluated throughout system level simulations and it is shown that Hybrid access contributes to seriously improve the performance of the whole network.
{"title":"A study of access methods effect on the performance of two-tier LTE femtocell networks","authors":"M. El- Gendy, E. Sourour","doi":"10.1109/NRSC.2011.5873600","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873600","url":null,"abstract":"Femtocells are a promising solution for the provision of high indoor coverage and capacity. Furthermore, OFDMA-based femtocells have proven to be highly versatile when dealing with cross-layer co-channel interference; however, concerns still exist related to the impact of the different access methods to femtocells in an overlaid network‥ Femtocells based on a Closed Subscribers group, where only device owners are allowed to connect, introduce severe interference to microcells' users. On the other hand, Open Access femtocells where any user can connect, does not bring many advantages to the femtocell owner [1]. In this paper, a study of the two types of access methods (Closed & Open Access) is proposed and a discussion of how to overcome their drawbacks by using the Hybrid access method is presented, which allows all users to connect but under restrictions. The performance of the model is evaluated throughout system level simulations and it is shown that Hybrid access contributes to seriously improve the performance of the whole network.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131508555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873615
S. El-Khamy, A.E. Youssef, M. Rizk
In this paper, it was intended to investigate the possibility of generating a random chaotic sequence, having a uniform histogram, using a chaotic sequence matching a given histogram and a chaotic sequence matching the complement of this histogram. To study the relation between these two sequences three methods are used to determine the complement of the histogram. Then based on the chaotic map tailoring synthesis method, the given histogram and a chosen starting point are used to generate the first chaotic sequence of a length L. The same procedure is repeated with the complement histogram to generate the second chaotic sequence of same length L. Histograms are computed for each of the sequences. The two generated chaotic sequences are then combined through simple interleaving resulting in a third sequence of length 2L whose histogram is then determined. The process is repeated for the two methods used to determine the complement histogram. Unlike expected, the third sequence histogram is not a uniform one. In the third method, to obtain a sequence having uniform histogram, it is found necessary to combine, through simple concatenation, two relatively computed different lengths of first and second chaotic sequences generated using original and complement histograms of the second or first methods.
{"title":"Generation of perfect random sequences using tailored chaotic maps","authors":"S. El-Khamy, A.E. Youssef, M. Rizk","doi":"10.1109/NRSC.2011.5873615","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873615","url":null,"abstract":"In this paper, it was intended to investigate the possibility of generating a random chaotic sequence, having a uniform histogram, using a chaotic sequence matching a given histogram and a chaotic sequence matching the complement of this histogram. To study the relation between these two sequences three methods are used to determine the complement of the histogram. Then based on the chaotic map tailoring synthesis method, the given histogram and a chosen starting point are used to generate the first chaotic sequence of a length L. The same procedure is repeated with the complement histogram to generate the second chaotic sequence of same length L. Histograms are computed for each of the sequences. The two generated chaotic sequences are then combined through simple interleaving resulting in a third sequence of length 2L whose histogram is then determined. The process is repeated for the two methods used to determine the complement histogram. Unlike expected, the third sequence histogram is not a uniform one. In the third method, to obtain a sequence having uniform histogram, it is found necessary to combine, through simple concatenation, two relatively computed different lengths of first and second chaotic sequences generated using original and complement histograms of the second or first methods.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130544203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-04-26DOI: 10.1109/NRSC.2011.5873637
A. Bayoumi, Y. Hanafy
As CMOS evolves from 32nm down to 16nm technologies, several technological changes suggest we can more efficiently use linear RC approximations to model the input stages of NMOS & PMOS. This improves the non-linearity of input stages of analog circuits such as RF amplifiers and buffers with input signal voltage levels, thus allowing better matching networks. This linearization is also critical when using fast spice in modeling the digital parts of a mixed signal RFICs. For physical gate lengths of 32 – 16nm, smaller gate area results in more pronounced role for overlap capacitance over source/drain (which is independent of voltage). Metal gates have replaced polysilicon, eliminating polysilicon depletion. This makes effective gate capacitance less voltage dependent in inversion. Metal gates have low resistivity, which makes non-quasi static characteristics easier to model and more uniform along the channel width, because of the reduction of the distributed gate resistance effect. Finally, using high dielectric constant (high-k) dielectrics to replace the thin gate oxides resulted in drastic reduction in gate leakage direct tunneling current, which is modeled as parallel conductance with an exponential dependence on applied gate voltage. In this paper, recently reported technology device features are used to update BSIM4 predictive technology models (PTM). The dependence of the NMOS & PMOS input equivalent circuits on applied biasing for 32–16nm gate lengths is simulated using SPICE circuit simulator.
{"title":"Bias dependence of NMOS and PMOS equivalent input circuits for 32–16nm gate length","authors":"A. Bayoumi, Y. Hanafy","doi":"10.1109/NRSC.2011.5873637","DOIUrl":"https://doi.org/10.1109/NRSC.2011.5873637","url":null,"abstract":"As CMOS evolves from 32nm down to 16nm technologies, several technological changes suggest we can more efficiently use linear RC approximations to model the input stages of NMOS & PMOS. This improves the non-linearity of input stages of analog circuits such as RF amplifiers and buffers with input signal voltage levels, thus allowing better matching networks. This linearization is also critical when using fast spice in modeling the digital parts of a mixed signal RFICs. For physical gate lengths of 32 – 16nm, smaller gate area results in more pronounced role for overlap capacitance over source/drain (which is independent of voltage). Metal gates have replaced polysilicon, eliminating polysilicon depletion. This makes effective gate capacitance less voltage dependent in inversion. Metal gates have low resistivity, which makes non-quasi static characteristics easier to model and more uniform along the channel width, because of the reduction of the distributed gate resistance effect. Finally, using high dielectric constant (high-k) dielectrics to replace the thin gate oxides resulted in drastic reduction in gate leakage direct tunneling current, which is modeled as parallel conductance with an exponential dependence on applied gate voltage. In this paper, recently reported technology device features are used to update BSIM4 predictive technology models (PTM). The dependence of the NMOS & PMOS input equivalent circuits on applied biasing for 32–16nm gate lengths is simulated using SPICE circuit simulator.","PeriodicalId":438638,"journal":{"name":"2011 28th National Radio Science Conference (NRSC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134294989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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