Spread spectrum

... Hopping Spread Spectrum FHSS): Hệ thống trải phổ bằng cách nhảy tần số sóng mang của nó trên một tập lớn các tần số, mẫu nhảy tần là giả ngẫu nhiên. Trải phổ dãy trực tiếp (Direct Sequence Spread Spectrum ... nào được dùng để truyền trong mỗi khung. Trải phổ nhảy tần Frequency Hopping Spread Spectrum Frequency Hopping Spread Spectrum (FHSS)Được phát minh bởi nữ diễn viên Holl...

Ngày tải lên: 13/09/2012, 11:16

... 19Direct Sequence Spread Spectrum Spread spectrum increases the bandwidth of the signal compared to narrow band by spreading the signal. ● There are two major types of spread spectrum techniques: ... 4Narrowband vs Spread SpectrumFrequencyPowerSpread Spectrum( Low Peak Power)Narrowband(High Peak Power) February 2005 Copyright 2005 All Rights Reserved 5Narrow Band vs Spread Sp...

Ngày tải lên: 13/09/2012, 11:16

... multi-carrier, spread spectrum and multi-carrier spread spectrum systems. We hope that this book will contribute to a better understanding of the principles of multi-carrier and spread spectrum and ... 1.3 Spread Spectrum Techniques 30 1.3.1 Direct Sequence Code Division Multiple Access 34 1.3.2 Advantages and Drawbacks of DS-CDMA 37 1.3.3 Applications of Spread Spectrum 3...

Ngày tải lên: 02/03/2013, 16:58

Ngày tải lên: 29/09/2013, 20:20

... requiring spread spectrum modulation: DSSS (Direct Sequence Spread Spectrum) and FHSS (Frequency Hopping Spread Spectrum) . Only the RF transmission has significant presence in the market. 1Mbps Spreading d t pn t DBPSK 11 ... (Small and Medium Organisations) interested in Spread Spectrum. These notes were used to introduce the SMO’s in the subject of Spread Spectrum. This Sp...

Ngày tải lên: 13/12/2013, 00:15

... constraint length K, rate and 2.6 Despreading with Matched Filters Despreading short spreading sequences with matched filters provides inherent code synchronization. The spreading waveform for a short ... Diversity 5.5 Rake Receiver 5.6 Error-Control Codes Diversity and Spread Spectrum 5.7 Problems 5.8 References 6 Code-Division Multiple Access 293 6.1 Spreading Sequences for DS/CDMA Orth...

Ngày tải lên: 20/01/2014, 06:20

Ngày tải lên: 19/02/2014, 14:20

... Spectrum Estimation 14.4 Nonparametric Spectrum Estimation Periodogram • The Bartlett Method • The Welch Method • Blackman-Tukey Method • Minimum Variance Spectrum Es- timator • Multiwindow Spectrum ... Spectrum Estimator 14.5 Parametric Spectrum Estimation Spectrum Estimation Based on Autoregressive Models • Spec- trum EstimationBasedon Moving AverageModels • Spectrum Estimat...

Ngày tải lên: 08/11/2013, 12:15

... 8 meter ' 3x10 8 f Hz ' 3x10 5 f kHz ' 300 f MHz ' 0.3 f GHz f Hz ' 3x10 8 8 meter f kHz ' 3x10 5 8 meter f MHz ' 300 8 meter f GHz ' 0.3 8 meter 2-3.1 Figure 1. Electromagnetic Radiation Spectrum FREQUENCY SPECTRUM Figure 1, which follows, depicts the electromagnetic radiation spectrum and some of the commonly used or known areas. ... microwave...

Ngày tải lên: 22/12/2013, 10:15

Ngày tải lên: 25/12/2013, 11:00