scholarly journals CLPDI Algorithm in UWB Synchronization

2021 ◽  
Author(s):  
Simone Soderi ◽  
Matti Hämäläinen ◽  
Jari Iinatti Iinatti
Keyword(s):  
Spread Spectrum ◽  
Performance Measure ◽  
Direct Sequence Spread Spectrum ◽  
Ultra Wideband ◽  
Acquisition Time ◽  
Spreading Code ◽  
Time Hopping ◽  
Acquisition Process ◽  
Large Bandwidth ◽  
Threshold Setting

<div> <div> <div> <p>This paper studies code synchronization in time hopping (TH) ultra wideband (UWB) systems. In TH UWB systems, narrow pulses based on Gaussian pulse are positioned in different locations in consecutive time frames. The location of each frame is defined by a spreading code. The receiver collects the energy of the pulses using the same spreading code. To be able to do that, it has to synchronize itself to the incoming signal. Due to the large bandwidth of the signal, several replicas of the signals arrive into the receiver. Thus, the energy of the signal is spread in time domain causing extra problems to the synchronization procedure. In this paper, earlierly proposed method for direct sequence spread spectrum system is applied for time hopping system. The method is simulated in a multipath environment. The performance measure used is the mean acquisition time. Con- stant false alarm rate criterion is used for the threshold setting rule for comparator. The energies of the multipath components are combined in the acquisition process. Therefore, diversity combining is obtained in the acquisition process, which also leads to performance improvement. </p> </div> </div> </div>

scholarly journals CLPDI Algorithm in UWB Synchronization

2021 ◽  
Author(s):  
Simone Soderi ◽  
Matti Hämäläinen ◽  
Jari Iinatti Iinatti
Keyword(s):  
Spread Spectrum ◽  
Performance Measure ◽  
Direct Sequence Spread Spectrum ◽  
Ultra Wideband ◽  
Acquisition Time ◽  
Spreading Code ◽  
Time Hopping ◽  
Acquisition Process ◽  
Large Bandwidth ◽  
Threshold Setting

<div> <div> <div> <p>This paper studies code synchronization in time hopping (TH) ultra wideband (UWB) systems. In TH UWB systems, narrow pulses based on Gaussian pulse are positioned in different locations in consecutive time frames. The location of each frame is defined by a spreading code. The receiver collects the energy of the pulses using the same spreading code. To be able to do that, it has to synchronize itself to the incoming signal. Due to the large bandwidth of the signal, several replicas of the signals arrive into the receiver. Thus, the energy of the signal is spread in time domain causing extra problems to the synchronization procedure. In this paper, earlierly proposed method for direct sequence spread spectrum system is applied for time hopping system. The method is simulated in a multipath environment. The performance measure used is the mean acquisition time. Con- stant false alarm rate criterion is used for the threshold setting rule for comparator. The energies of the multipath components are combined in the acquisition process. Therefore, diversity combining is obtained in the acquisition process, which also leads to performance improvement. </p> </div> </div> </div>

scholarly journals Performance Analysis and Comparison of Full Chip and Half Chip Rate DC and NC Code Acquisition in MIMO DSCDMA over Uncorrelated Rayleigh Wireless Channel

2011 ◽  
Vol 2011 ◽  
pp. 1-8
Author(s):  
N. Sathish Kumar ◽  
K. R. Shankar Kumar
Keyword(s):  
Performance Analysis ◽  
Spread Spectrum ◽  
Performance Metrics ◽  
Multiple Input Multiple Output ◽  
Direct Sequence Spread Spectrum ◽  
Wireless Channel ◽  
Acquisition Time ◽  
Code Acquisition ◽  
Nc Code ◽  
Input Multiple Output

This paper presents the performance analysis and comparison of full chip and half chip rate of noncoherent (NC) and differentially coherent (DC) code acquisition scheme in (multiple input-multiple output) MIMO assisted by direct sequence spread spectrum (DS-CDMA) wireless system when communicated over uncorrelated Rayleigh channel. Four schemes are investigated, namely, SISO with full chip rate, SISO with Half chip rate, MIMO with full chip rate, and MIMO with half chip rate by varying the code acquisition technique. The simulation is done in RF signal processing Lab using matlab tool box, and the performance metrics are considered, namely, Bit Error Rate (BER) and mean acquisition time (MAT). The simulation results indicate that DC performance is superior than NC in both full chip and half chip rate and also shown that half chip performance is better than full chip in both DC and NC code acquisition methods.

scholarly journals Analysis and optimization of direct sequence spread spectrum scheme for an unmanned aerial vehicle PPM control signal

2010 ◽  
Vol 23 (3) ◽  
pp. 319-332
Author(s):  
Branislav Todorovic ◽  
Vladimir Orlic
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Spread Spectrum ◽  
Performance Measure ◽  
Direct Sequence Spread Spectrum ◽  
Control Signal ◽  
False Alarms ◽  
Direct Sequence ◽  
Aerial Vehicles ◽  
Aerial Vehicle ◽  
Pn Sequences

Binary pulse-position modulated (PPM) control signal is widely used in remotely controlled unmanned aerial vehicles. It consists of data frames, which contain a synchronizing pulse followed by a number of shorter pulses equal to the number of channels N. In this paper we present analysis and optimization of direct sequence spread spectrum (DS-SS) scheme for PPM control signal protection. That scheme uses (N+1) pseudonoise (PN) sequences: one of them (PN0) is assigned to the synchronizing pulse while the each of the remaining N sequences (PN1,PN2, . . . ,PNN) corresponds to the appropriate channel. At the receiving side, the set of (N+1) passive correlators is used to detect respective PN sequences and to reconstruct data. Onelevel and two-level detection are considered. Threshold settings optimization is based on the Neyman-Pearson procedure. As an additional performance measure we introduce probability of corruptive false alarms. Numerical results are presented.

scholarly journals Optimization of Spreading Code using Modified Differential Evolution for Wireless Communication

2021 ◽  
Author(s):  
Katyayani Kashyap ◽  
Sunil Pathak ◽  
Narender Yadav
Keyword(s):  
Wireless Communication ◽  
Bit Error Rate ◽  
Spread Spectrum ◽  
Logistic Map ◽  
Direct Sequence Spread Spectrum ◽  
Optimization Techniques ◽  
Spreading Code ◽  
Direct Sequence ◽  
Design Problems ◽  
Engineering Design Problems

Abstract Spread spectrum linked to optimization techniques play a very important role in today’s world. Optimization gives the best one among all the solutions and the spread spectrum is used to minimize distortion, hence optimized spreading code is very important in wireless communication. This study shows a comparison of two recent modified techniques of DE with the help of engineering design problems and application of that modified DE (considering the better one) in wireless communication to optimize logistic map based spreading code. A comparative study of properties of both optimized and non-optimized spreading code is also discussed in this paper. The performance of the optimized spreading code is also evaluated with the help of bit error rate (BER) by applying it in static and dynamic direct sequence spread spectrum system (DSSS). The performance of the proposed technique (optimized dynamic logistic map code based DSSS) displays better results than non-optimized spreading code and orthogonal spreading code considering BER. Therefore, the proposed method can be efficiently applied in the wireless communication system.

Sign in / Sign up

Export Citation Format

Share Document