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2008 Vol. 30, No. 4
Display Method:
2008, 30(4): 763-767.
doi: 10.3724/SP.J.1146.2006.01604
Abstract:
This paper investigates the distributed allocation control of multi-access channel in broadband satellite mesh network. A novel combined Dynamic Allocation Multi-Access (DAMA) scheme is proposed, which is based on the chaotic prediction of self-simil...
This paper investigates the distributed allocation control of multi-access channel in broadband satellite mesh network. A novel combined Dynamic Allocation Multi-Access (DAMA) scheme is proposed, which is based on the chaotic prediction of self-simil...
2008, 30(4): 768-771.
doi: 10.3724/SP.J.1146.2006.01467
Abstract:
In this paper, digital part of LEO CDMA satellite transmitter is researched, and its structure, algorithm and implementation are introduced.The emphasis is pressed upon implementation of signal processing part of the digital transmitter, especially u...
In this paper, digital part of LEO CDMA satellite transmitter is researched, and its structure, algorithm and implementation are introduced.The emphasis is pressed upon implementation of signal processing part of the digital transmitter, especially u...
2008, 30(4): 772-775.
doi: 10.3724/SP.J.1146.2006.01492
Abstract:
This paper discusses the feasibility of LEO satellite of fixation antenna and low or middle power accessing to the TDRSS and realizing space-ground data transmission through TDRS. The precondition of communication between LEO satellite and TDRS are g...
This paper discusses the feasibility of LEO satellite of fixation antenna and low or middle power accessing to the TDRSS and realizing space-ground data transmission through TDRS. The precondition of communication between LEO satellite and TDRS are g...
2008, 30(4): 776-779.
doi: 10.3724/SP.J.1146.2006.01590
Abstract:
In practical wireless communication networks, downlink beamforming weights at the node B of smart antenna systems can be deteriorated due to variation of spatial signal vectors corresponding to mobile users or DOA estimation error. In this paper, the...
In practical wireless communication networks, downlink beamforming weights at the node B of smart antenna systems can be deteriorated due to variation of spatial signal vectors corresponding to mobile users or DOA estimation error. In this paper, the...
2008, 30(4): 780-783.
doi: 10.3724/SP.J.1146.2005.01603
Abstract:
The incremental redundancy type-II HARQ has been applied into the cross layer design. The closed-form expressions of the packet error rate and average spectral efficiency for the transmissions over Nakagami- channel have been derived. Numerical resul...
The incremental redundancy type-II HARQ has been applied into the cross layer design. The closed-form expressions of the packet error rate and average spectral efficiency for the transmissions over Nakagami- channel have been derived. Numerical resul...
2008, 30(4): 784-787.
doi: 10.3724/SP.J.1146.2006.01487
Abstract:
Based on the minimum Bit Error Rate (BER) criterion, a greedy bit allocation algorithm and bisection-method based bit allocation algorithm are proposed for Multiple-Input Multiple-Output (MIMO) spatial multiplexing systems. Under the constraint of to...
Based on the minimum Bit Error Rate (BER) criterion, a greedy bit allocation algorithm and bisection-method based bit allocation algorithm are proposed for Multiple-Input Multiple-Output (MIMO) spatial multiplexing systems. Under the constraint of to...
2008, 30(4): 788-791.
doi: 10.3724/SP.J.1146.2006.01583
Abstract:
In this paper, the scheduling strategy of minimizing power under delay constraint is proposed in wireless channel. The problem is first formulated as an unconstrained Markov Decision Process（MDP）and solved by dynamic programming. But its final decisi...
In this paper, the scheduling strategy of minimizing power under delay constraint is proposed in wireless channel. The problem is first formulated as an unconstrained Markov Decision Process（MDP）and solved by dynamic programming. But its final decisi...
2008, 30(4): 792-796.
doi: 10.3724/SP.J.1146.2006.01538
Abstract:
When PABT (Pilot-Assisted Block Transmission) signal is transmitted over severe multipath channels, consecutive pilot block and data block may partially overlap each other. If no guard interval is inserted between them, a process to cancel the mutual...
When PABT (Pilot-Assisted Block Transmission) signal is transmitted over severe multipath channels, consecutive pilot block and data block may partially overlap each other. If no guard interval is inserted between them, a process to cancel the mutual...
2008, 30(4): 797-800.
doi: 10.3724/SP.J.1146.2006.01478
Abstract:
Based on the m-sequence，a time-domain channel estimation algorithm for Multi-Input Multi-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) is designed. The m-sequence with Cyclic Prefix (CP) is inserted between OFDM symbols in time domain...
Based on the m-sequence，a time-domain channel estimation algorithm for Multi-Input Multi-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) is designed. The m-sequence with Cyclic Prefix (CP) is inserted between OFDM symbols in time domain...
2008, 30(4): 801-804.
doi: 10.3724/SP.J.1146.2006.01465
Abstract:
Triangular Cell Communication System (TCCS) is a novel distributed Base Station (BS) system. Its cell structure is an equilateral triangle, and it is composed of 3 Uni-Cover Regions (UCR) and 1 Cross-Covered Region (CCR). Mobile Station (MS) communic...
Triangular Cell Communication System (TCCS) is a novel distributed Base Station (BS) system. Its cell structure is an equilateral triangle, and it is composed of 3 Uni-Cover Regions (UCR) and 1 Cross-Covered Region (CCR). Mobile Station (MS) communic...
2008, 30(4): 805-808.
doi: 10.3724/SP.J.1146.2006.01518
Abstract:
Based on Ultra-WideBand (UWB) conventional Transmitted Reference (TR) technology, the interference model which reference and data receive waveforms are both contaminated by inter-pulse interference is analyzed relying on Time Division Multiple Access...
Based on Ultra-WideBand (UWB) conventional Transmitted Reference (TR) technology, the interference model which reference and data receive waveforms are both contaminated by inter-pulse interference is analyzed relying on Time Division Multiple Access...
2008, 30(4): 809-813.
doi: 10.3724/SP.J.1146.2006.01521
Abstract:
The selection of cooperative partner is a key problem in the cooperative network. All the former solutions to this problem in essence base on the performance of the transceiver while neglecting the fairness among the cooperative partners. In this pap...
The selection of cooperative partner is a key problem in the cooperative network. All the former solutions to this problem in essence base on the performance of the transceiver while neglecting the fairness among the cooperative partners. In this pap...
2008, 30(4): 814-816.
doi: 10.3724/SP.J.1146.2006.01601
Abstract:
This paper presents two kinds of methods for constructing perfect ternary array pairs by using perfect ternary array pairs properties. They are periodic multiplication of perfect ternary array pairs and recursing construction of perfect ternary array...
This paper presents two kinds of methods for constructing perfect ternary array pairs by using perfect ternary array pairs properties. They are periodic multiplication of perfect ternary array pairs and recursing construction of perfect ternary array...
2008, 30(4): 817-821.
doi: 10.3724/SP.J.1146.2006.01531
Abstract:
This paper introduces a single-carrier system with hybrid time-frequency domain Decision Feedback Equalization (DFE), in which the short pn (Pseudo-Noise) sequence with fixed waveform replaces the cyclic prefix (CP) in the conventional Single Carrier...
This paper introduces a single-carrier system with hybrid time-frequency domain Decision Feedback Equalization (DFE), in which the short pn (Pseudo-Noise) sequence with fixed waveform replaces the cyclic prefix (CP) in the conventional Single Carrier...
2008, 30(4): 822-825.
doi: 10.3724/SP.J.1146.2006.01505
Abstract:
Digital fountain is a packet oriented forward error correction technology for channels with erasures, which has obvious efficiency advantage in broadcast. In the paper, LDPC code is put into practice in digital fountain encoding, and a fast decoding ...
Digital fountain is a packet oriented forward error correction technology for channels with erasures, which has obvious efficiency advantage in broadcast. In the paper, LDPC code is put into practice in digital fountain encoding, and a fast decoding ...
2008, 30(4): 826-830.
doi: 10.3724/SP.J.1146.2006.01416
Abstract:
A class of structured irregular Low-Density Parity-Check (LDPC) codes with high performance and low complexity is proposed in this paper. First, a global matrix M with a triangular plus dual-diagonal form based on Improved eIRA (IeIRA) method is desi...
A class of structured irregular Low-Density Parity-Check (LDPC) codes with high performance and low complexity is proposed in this paper. First, a global matrix M with a triangular plus dual-diagonal form based on Improved eIRA (IeIRA) method is desi...
2008, 30(4): 831-835.
doi: 10.3724/SP.J.1146.2006.01586
Abstract:
Based on the FFT of a single-tone sequence, this paper presents a novel Moving Average Maximum Likelihood (MAML) frequency estimator, which develops a Moving Average (MA) model by the real part relationship between different significant FFT coefficie...
Based on the FFT of a single-tone sequence, this paper presents a novel Moving Average Maximum Likelihood (MAML) frequency estimator, which develops a Moving Average (MA) model by the real part relationship between different significant FFT coefficie...
2008, 30(4): 836-839.
doi: 10.3724/SP.J.1146.2006.01490
Abstract:
In this paper, the sensitivity of MAP algorithm and its reduced ones as Max-Log-MAP and Scaled Max-Log-Map to SNR mismatch in turbo detection systems are analyzed. Due to the fact of insensitivity of Scaled Max-Log-MAP algorithm to SNR mismatch, a ne...
In this paper, the sensitivity of MAP algorithm and its reduced ones as Max-Log-MAP and Scaled Max-Log-Map to SNR mismatch in turbo detection systems are analyzed. Due to the fact of insensitivity of Scaled Max-Log-MAP algorithm to SNR mismatch, a ne...
2008, 30(4): 840-842.
doi: 10.3724/SP.J.1146.2006.01345
Abstract:
Based on the periodicity that the signals which are gotten by doing delay-multiply with the Direct Sequence Spread Spectral (DSSS) signals, the paper proposes an efficient method for the detection of DSSS signals: the detection, symbol period and chi...
Based on the periodicity that the signals which are gotten by doing delay-multiply with the Direct Sequence Spread Spectral (DSSS) signals, the paper proposes an efficient method for the detection of DSSS signals: the detection, symbol period and chi...
2008, 30(4): 843-847.
doi: 10.3724/SP.J.1146.2006.00925
Abstract:
Recently, a Multiple Symbol Differential Sphere Decoding (MSDSD) algorithm for unitary space-time modulation over quasi-static channel is proved to achieve the performance of Maximum-Likelihood (ML) detection with relatively low complexity. However, ...
Recently, a Multiple Symbol Differential Sphere Decoding (MSDSD) algorithm for unitary space-time modulation over quasi-static channel is proved to achieve the performance of Maximum-Likelihood (ML) detection with relatively low complexity. However, ...
2008, 30(4): 848-852.
doi: 10.3724/SP.J.1146.2006.01403
Abstract:
Multi-Lag High-order Instantaneous Moment (ML-HIM), an encoding method removing signal phase ambiguity, can correct not only the constant phase offset but also Doppler frequency shift. Differential coding method can mitigate constant phase offset exc...
Multi-Lag High-order Instantaneous Moment (ML-HIM), an encoding method removing signal phase ambiguity, can correct not only the constant phase offset but also Doppler frequency shift. Differential coding method can mitigate constant phase offset exc...
2008, 30(4): 853-858.
doi: 10.3724/SP.J.1146.2006.01408
Abstract:
The researches of FREquency-SHift (FRESH) filter are usually based on the hypothesis that the receivers precisely know the cycle frequencies of signal or interference. However, in the practical application circumstances of FRESH filter, Cycle Frequen...
The researches of FREquency-SHift (FRESH) filter are usually based on the hypothesis that the receivers precisely know the cycle frequencies of signal or interference. However, in the practical application circumstances of FRESH filter, Cycle Frequen...
2008, 30(4): 859-862.
doi: 10.3724/SP.J.1146.2006.01519
Abstract:
Spatial smoothing techniques are effective to estimate the directions of coherent arrivals. The performance of these techniques deteriorates rapidly as the coherent arrivals become closely spaced. In this correspondence, an improved spatial smoothing...
Spatial smoothing techniques are effective to estimate the directions of coherent arrivals. The performance of these techniques deteriorates rapidly as the coherent arrivals become closely spaced. In this correspondence, an improved spatial smoothing...
2008, 30(4): 863-867.
doi: 10.3724/SP.J.1146.2006.01414
Abstract:
This paper gives a new method to estimate the number of source signals and recover them by the characteristics of sparse source signals in underdetermined blind separation. It is well known that source signals can be recovered through the two-step al...
This paper gives a new method to estimate the number of source signals and recover them by the characteristics of sparse source signals in underdetermined blind separation. It is well known that source signals can be recovered through the two-step al...
2008, 30(4): 868-871.
doi: 10.3724/SP.J.1146.2006.01412
Abstract:
The problem of estimating the phase parameters of chirp signals embedded in noise is concerned in this paper. The computationally efficient cyclostationary estimation method is introduced, and in order to avoid its disadvantages, an iterative estimat...
The problem of estimating the phase parameters of chirp signals embedded in noise is concerned in this paper. The computationally efficient cyclostationary estimation method is introduced, and in order to avoid its disadvantages, an iterative estimat...
2008, 30(4): 872-875.
doi: 10.3724/SP.J.1146.2006.01398
Abstract:
A decision-theoretic based scheme is developed for modulation classification in a fading environment. The proposed method takes into account a flat Rayleigh fading propagation channel. The likelihood function is derived according to the channel and s...
A decision-theoretic based scheme is developed for modulation classification in a fading environment. The proposed method takes into account a flat Rayleigh fading propagation channel. The likelihood function is derived according to the channel and s...
2008, 30(4): 876-880.
doi: 10.3724/SP.J.1146.2006.01339
Abstract:
Conjugate Extended MUSIC (CE-MUSIC) and MUSIC-like algorithm can be used to estimate the directions of arrival of noncircular signals (e.g. BPSK modulated signals) which are widely used in communication systems. The performance of these two algorithm...
Conjugate Extended MUSIC (CE-MUSIC) and MUSIC-like algorithm can be used to estimate the directions of arrival of noncircular signals (e.g. BPSK modulated signals) which are widely used in communication systems. The performance of these two algorithm...
2008, 30(4): 881-884.
doi: 10.3724/SP.J.1146.2006.01240
Abstract:
The two-dimensional ADBF method at subarray level is studied. The signal model of ADBF at subarray level is presented which is suitable for plane phased array. The conventional two-dimensional ADBF at subarray level is given which is generalized by o...
The two-dimensional ADBF method at subarray level is studied. The signal model of ADBF at subarray level is presented which is suitable for plane phased array. The conventional two-dimensional ADBF at subarray level is given which is generalized by o...
2008, 30(4): 885-888.
doi: 10.3724/SP.J.1146.2006.01453
Abstract:
Wavelet-based image denoising algorithms is a hot point in image processing applications. In this paper, a doubly local Wiener filtering algorithm using elliptic directional window and mathematical morphology is proposed, in which the mathematical mo...
Wavelet-based image denoising algorithms is a hot point in image processing applications. In this paper, a doubly local Wiener filtering algorithm using elliptic directional window and mathematical morphology is proposed, in which the mathematical mo...
2008, 30(4): 889-892.
doi: 10.3724/SP.J.1146.2006.01482
Abstract:
Single orbit bistaitc space based radar is composed of two radars in the same orbit. The paper analyzes the clutter angle-Doppler spectrum in this radar system, and finds out that minimum detectable velocity(MDV) is dependent on detecting angles and ...
Single orbit bistaitc space based radar is composed of two radars in the same orbit. The paper analyzes the clutter angle-Doppler spectrum in this radar system, and finds out that minimum detectable velocity(MDV) is dependent on detecting angles and ...
2008, 30(4): 893-897.
doi: 10.3724/SP.J.1146.2006.01532
Abstract:
This paper deals with the influence of ground fluctuation and roughness on the correlation between distributed Satellites SAR echoes. The model for a rough surface is presented based on the facet theory followed by the analysis of its statistical sca...
This paper deals with the influence of ground fluctuation and roughness on the correlation between distributed Satellites SAR echoes. The model for a rough surface is presented based on the facet theory followed by the analysis of its statistical sca...
2008, 30(4): 898-901.
doi: 10.3724/SP.J.1146.2006.01483
Abstract:
Since factors such as turbulence and pilot error make it impossible for an aircraft to flight along the nominal straight flight path, SAR motion compensation technology is crucial to acquiring high quality image. When the aircraft changes in the roll...
Since factors such as turbulence and pilot error make it impossible for an aircraft to flight along the nominal straight flight path, SAR motion compensation technology is crucial to acquiring high quality image. When the aircraft changes in the roll...
2008, 30(4): 902-905.
doi: 10.3724/SP.J.1146.2006.01418
Abstract:
It is known that for Linear Frequency Modulation (LFM) Synthetic Aperture Radar (SAR) echo signal, the obtained SAR image by 2-dimensional matched filtering has relatively high sidelobe level. Though such sidelobe can be depressed with amplitude weig...
It is known that for Linear Frequency Modulation (LFM) Synthetic Aperture Radar (SAR) echo signal, the obtained SAR image by 2-dimensional matched filtering has relatively high sidelobe level. Though such sidelobe can be depressed with amplitude weig...
2008, 30(4): 906-910.
doi: 10.3724/SP.J.1146.2007.00424
Abstract:
Space-Time Adaptive Processing (STAP) is a key technology for moving target detection, but nonhomogeneity will cause the covariance matrix estimation error, which substantially results in the STAP performance degradation. Diagonal loading is used as ...
Space-Time Adaptive Processing (STAP) is a key technology for moving target detection, but nonhomogeneity will cause the covariance matrix estimation error, which substantially results in the STAP performance degradation. Diagonal loading is used as ...
2008, 30(4): 911-915.
doi: 10.3724/SP.J.1146.2006.01684
Abstract:
In this paper, the focusing has been on spatial interpolation in correcting atmospheric effects using Interferometric SAR based on external data. Several factors have been discussed separately by using both simulated data and GPS data. The results in...
In this paper, the focusing has been on spatial interpolation in correcting atmospheric effects using Interferometric SAR based on external data. Several factors have been discussed separately by using both simulated data and GPS data. The results in...
2008, 30(4): 916-920.
doi: 10.3724/SP.J.1146.2006.00927
Abstract:
Dechirping is an effective method for decreasing the bandwidth of input signals. For high velocity moving targets ISAR imaging, the residual phase arisen from dechirping processing and target moving can not be ignored. The theoretic model of phase si...
Dechirping is an effective method for decreasing the bandwidth of input signals. For high velocity moving targets ISAR imaging, the residual phase arisen from dechirping processing and target moving can not be ignored. The theoretic model of phase si...
2008, 30(4): 921-924.
doi: 10.3724/SP.J.1146.2006.01607
Abstract:
It is difficult to directly compress Synthetic Aperture Radar (SAR) raw data for its low relativity. In this paper, a new algorithm is put forward. Range focusing is imposed to SAR raw data, which makes it have comparative high relativity, then a vec...
It is difficult to directly compress Synthetic Aperture Radar (SAR) raw data for its low relativity. In this paper, a new algorithm is put forward. Range focusing is imposed to SAR raw data, which makes it have comparative high relativity, then a vec...
2008, 30(4): 925-928.
doi: 10.3724/SP.J.1146.2006.00920
Abstract:
Ground Penetrating Synthetic Aperture Radar (GPSAR), working in low frequency, has the capability of ground penetrating to obtain the two-dimensional high-resolution image of shallow buried targets. Vehicle-borne forward-looking GPSAR can detect land...
Ground Penetrating Synthetic Aperture Radar (GPSAR), working in low frequency, has the capability of ground penetrating to obtain the two-dimensional high-resolution image of shallow buried targets. Vehicle-borne forward-looking GPSAR can detect land...
2008, 30(4): 929-932.
doi: 10.3724/SP.J.1146.2007.01314
Abstract:
The APP method is capable to provide excellent estimation of speech aperiodic / periodic measurement and pitch simultaneously which is useful in speech research and application. However, due to its heavy computational load, APP system is about 110 ti...
The APP method is capable to provide excellent estimation of speech aperiodic / periodic measurement and pitch simultaneously which is useful in speech research and application. However, due to its heavy computational load, APP system is about 110 ti...
2008, 30(4): 933-936.
doi: 10.3724/SP.J.1146.2006.01463
Abstract:
In this paper, a digital watermarking algorithm resistant to the noise, geometric distortion and JPEG compression is proposed. Firstly, in order to enhance the security of the watermarking, the original meaningful binary image watermarking is scrambl...
In this paper, a digital watermarking algorithm resistant to the noise, geometric distortion and JPEG compression is proposed. Firstly, in order to enhance the security of the watermarking, the original meaningful binary image watermarking is scrambl...
2008, 30(4): 937-940.
doi: 10.3724/SP.J.1146.2006.01397
Abstract:
Many researchers have found it can improve the retrieval performance by combining region-based representation and relevance feedback technology. Since the previous works have ignored the probabilistic distribution of regions in the same semantic clas...
Many researchers have found it can improve the retrieval performance by combining region-based representation and relevance feedback technology. Since the previous works have ignored the probabilistic distribution of regions in the same semantic clas...
2008, 30(4): 941-944.
doi: 10.3724/SP.J.1146.2006.01528
Abstract:
Track-Before-Detect(TBD) is an efficient approach which detects and tracks targets in low SNR environment. A multiple model particle filter algorithm is presented in this paper for the maneuvering weak target which dynamics is complicated. In this al...
Track-Before-Detect(TBD) is an efficient approach which detects and tracks targets in low SNR environment. A multiple model particle filter algorithm is presented in this paper for the maneuvering weak target which dynamics is complicated. In this al...
2008, 30(4): 945-948.
doi: 10.3724/SP.J.1146.2006.01513
Abstract:
A low bit-rate real time video encoding system on MPEG using DSP TMS320DM642 as core processor is designed. The main features are: Diamond Search is integrated with Center-based Three-step Search (CTSS); A new method for pre-determination of all-zero...
A low bit-rate real time video encoding system on MPEG using DSP TMS320DM642 as core processor is designed. The main features are: Diamond Search is integrated with Center-based Three-step Search (CTSS); A new method for pre-determination of all-zero...
2008, 30(4): 949-952.
doi: 10.3724/SP.J.1146.2006.01468
Abstract:
A novel contour-based shape description and matching method is proposed. It equally segments the contours of the two objects into same numbers of arcs, an approximating polygon is then constructed with connecting the neighbor segmenting points using ...
A novel contour-based shape description and matching method is proposed. It equally segments the contours of the two objects into same numbers of arcs, an approximating polygon is then constructed with connecting the neighbor segmenting points using ...
2008, 30(4): 953-956.
doi: 10.3724/SP.J.1146.2006.01597
Abstract:
During tracking dim and small moving targets in the electrooptical detecting system, many false alarms extracted in the tracking window for low signal-to-noise ratio and high false alarm ratio debase seriously the performance of target recognition an...
During tracking dim and small moving targets in the electrooptical detecting system, many false alarms extracted in the tracking window for low signal-to-noise ratio and high false alarm ratio debase seriously the performance of target recognition an...
2008, 30(4): 957-960.
doi: 10.3724/SP.J.1146.2007.00845
Abstract:
An MERF based edge detection algorithm with adaptive threshold is presented in this paper. After analyzing dyadic wavelet transform and different behavior of edge and noise across scales, a Multi-scale Edge Response Function (MERF) is defined as the ...
An MERF based edge detection algorithm with adaptive threshold is presented in this paper. After analyzing dyadic wavelet transform and different behavior of edge and noise across scales, a Multi-scale Edge Response Function (MERF) is defined as the ...
2008, 30(4): 961-965.
doi: 10.3724/SP.J.1146.2007.00184
Abstract:
A backoff algorithm based on Minimum Contention Window Self-adaptive Adjusting (MCWSA) is proposed in this paper. The idea of this algorithm is that every node in the network adjusts self minimum contention window periodically, according to the compa...
A backoff algorithm based on Minimum Contention Window Self-adaptive Adjusting (MCWSA) is proposed in this paper. The idea of this algorithm is that every node in the network adjusts self minimum contention window periodically, according to the compa...
2008, 30(4): 966-969.
doi: 10.3724/SP.J.1146.2006.01552
Abstract:
Based on the strict energy limitations in wireless sensor network, how to decide the number of clusters, which is influenced with the total number of sensors and the characteristics of the disposed area, is the key idea in clustering algorithm. The e...
Based on the strict energy limitations in wireless sensor network, how to decide the number of clusters, which is influenced with the total number of sensors and the characteristics of the disposed area, is the key idea in clustering algorithm. The e...
2008, 30(4): 970-974.
doi: 10.3724/SP.J.1146.2006.01511
Abstract:
DV-Hop algorithm is one of the important range-free localization algorithms. The algorithm performs better in isotropic density sensor networks, however, it has larger location errors in randomly distributed networks. According to the localization pr...
DV-Hop algorithm is one of the important range-free localization algorithms. The algorithm performs better in isotropic density sensor networks, however, it has larger location errors in randomly distributed networks. According to the localization pr...
2008, 30(4): 975-978.
doi: 10.3724/SP.J.1146.2006.01431
Abstract:
Multiple dimension packet classification is an enabling function for many Internet applications, such as network security, network monitoring, quality of service, flow routing, etc. It is difficult to develop a packet classification algorithm that is...
Multiple dimension packet classification is an enabling function for many Internet applications, such as network security, network monitoring, quality of service, flow routing, etc. It is difficult to develop a packet classification algorithm that is...
2008, 30(4): 979-983.
doi: 10.3724/SP.J.1146.2006.01422
Abstract:
Priority classification and two-level collision being adopted, Enhanced Distributed Channel Access (EDCA)mechanism of IEEE 802.11e protocol is quite difficult to be modeled and analyzed. According to the characteristics of EDCA mechanism, an effectiv...
Priority classification and two-level collision being adopted, Enhanced Distributed Channel Access (EDCA)mechanism of IEEE 802.11e protocol is quite difficult to be modeled and analyzed. According to the characteristics of EDCA mechanism, an effectiv...
2008, 30(4): 984-987.
doi: 10.3724/SP.J.1146.2006.01254
Abstract:
This paper combines firstly priority control mechanism into integrated service dual token ring LAN, constructs queuing model, and then gets mathematical solving and simulation results for dual token ring LAN of three priorities, and gets important fa...
This paper combines firstly priority control mechanism into integrated service dual token ring LAN, constructs queuing model, and then gets mathematical solving and simulation results for dual token ring LAN of three priorities, and gets important fa...
2008, 30(4): 988-990.
doi: 10.3724/SP.J.1146.2006.01464
Abstract:
There usually exists the coupling temporal arrearage circs in the real network owing to the congestion, bandwidth and transmission velocity. Therefore, one new kinds of cascading failure model with the coupling temporal arrearage character is come in...
There usually exists the coupling temporal arrearage circs in the real network owing to the congestion, bandwidth and transmission velocity. Therefore, one new kinds of cascading failure model with the coupling temporal arrearage character is come in...
2008, 30(4): 991-994.
doi: 10.3724/SP.J.1146.2006.01507
Abstract:
The precise definition and security model of a new signature scheme－limited confederate verifier signatures is proposed based on the idea of threshold. An efficient limited confederate verifier signatures scheme is also constructed for the first time...
The precise definition and security model of a new signature scheme－limited confederate verifier signatures is proposed based on the idea of threshold. An efficient limited confederate verifier signatures scheme is also constructed for the first time...
2008, 30(4): 995-998.
doi: 10.3724/SP.J.1146.2007.00549
Abstract:
In this paper, the concepts of identity-based linkable ring signature and linkable convertible ring signature are proposed. Taken Zhang and Kims scheme as an example, a general method is given to add linkability and convertibility to some identity-ba...
In this paper, the concepts of identity-based linkable ring signature and linkable convertible ring signature are proposed. Taken Zhang and Kims scheme as an example, a general method is given to add linkability and convertibility to some identity-ba...
2008, 30(4): 999-1003.
doi: 10.3724/SP.J.1146.2006.01454
Abstract:
In this paper, a novel splitting technique of ray tubes based on ray tracing method is put forward, which is called the deterministic splitting method of ray tubes. At the same time, the analytic splitting format and the demonstration of self-contain...
In this paper, a novel splitting technique of ray tubes based on ray tracing method is put forward, which is called the deterministic splitting method of ray tubes. At the same time, the analytic splitting format and the demonstration of self-contain...
2008, 30(4): 1004-1006.
doi: 10.3724/SP.J.1146.2007.00673
Abstract:
Based on the percentage amplitude mismatch, the approximate BER formula of the Successive Interference Canceller (SIC) is presented with the Gaussian approximation method，and the effect of the amplitude mismatch on the Bit Error Rate (BER) performanc...
Based on the percentage amplitude mismatch, the approximate BER formula of the Successive Interference Canceller (SIC) is presented with the Gaussian approximation method，and the effect of the amplitude mismatch on the Bit Error Rate (BER) performanc...
2008, 30(4): 1007-1010.
doi: 10.3724/SP.J.1146.2006.01656
Abstract:
In this paper, AP (Amplitude-Phase) algorithm for SAR raw data compression is studied and the formula of bit allocation between amplitude data and phase data is deduced based on the lower bound of rate-distortion inequality of non-normal information ...
In this paper, AP (Amplitude-Phase) algorithm for SAR raw data compression is studied and the formula of bit allocation between amplitude data and phase data is deduced based on the lower bound of rate-distortion inequality of non-normal information ...
2008, 30(4): 1011-1013.
doi: 10.3724/SP.J.1146.2006.01390
Abstract:
In this paper, the theoretical analyses and simulations of the SAR imaging processing are firstly made, the time-domain sub-aperture algorithm which is used to implement missile-borne SAR, are researched and the whole flow of the algorithm are given....
In this paper, the theoretical analyses and simulations of the SAR imaging processing are firstly made, the time-domain sub-aperture algorithm which is used to implement missile-borne SAR, are researched and the whole flow of the algorithm are given....
2008, 30(4): 1014-1016.
doi: 10.3724/SP.J.1146.2006.01311
Abstract:
Based on the numerical simulation model of OCPAR and paired-echo theory, the phase fluctuation of optic-link, and the pattern and pulse compression of an array, which are influenced by optic-links phase characteristics, are analyzed theoretically and...
Based on the numerical simulation model of OCPAR and paired-echo theory, the phase fluctuation of optic-link, and the pattern and pulse compression of an array, which are influenced by optic-links phase characteristics, are analyzed theoretically and...
