narrowband broadband and spread spectrum signals

... and Spread Spectrum Systems K Fazel Marconi Communications GmbH Germany and S Kaiser German Aerospace Center (DLR) Germany Multi-Carrier and Spread Spectrum Systems Multi-Carrier and Spread Spectrum ... 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 may motivate further investigation into and ... frequency fDmax and the Doppler spread fDspread The Doppler spread is the bandwidth of the Doppler power density spectrum and can take on values up to two times |fDmax |, i.e., fDspread 2|fDmax...

Ngày tải lên: 02/03/2013, 16:58

... frequency fDmax and the Doppler spread fDspread The Doppler spread is the bandwidth of the Doppler power density spectrum and can take on values up to two times |fDmax |, i.e., fDspread 2|fDmax ... station compatibility standard for dual mode wideband spread spectrum cellular system,” July 1993 [44] TIA/EIA/IS-cdma2000, “Physical layer standard for cdma2000 spread spectrum systems,” Aug ... Applications and Standards The key parameters of various multi-carrier-based communications standards for broadcasting, WLAN and WLL, are summarized in Tables 1-2 to 1-4 1.3 Spread Spectrum Techniques Spread...

Ngày tải lên: 09/08/2014, 19:22

... The MC-DS-CDMA schemes can be subdivided in schemes with broadband sub-channels and schemes with narrowband sub-channels Systems with broadband sub-channels typically apply only few numbers of sub-channels, ... multi-carrier spread spectrum have been proposed [23][24] More potential application fields for multi-carrier spread spectrum are in wireless indoor communications [50] and broadband underwater ... compatibility standard for dual mode wideband spread spectrum cellular system,” July 1993 References 47 [43] Turin G.L., “Introduction to spread spectrum anti-multipath techniques and their application...

Ngày tải lên: 09/08/2014, 19:22

... narrowband and the fading per sub-channel appears flat and in systems with broadband sub-channels where the fading is frequency-selective per sub-channel The fading over the whole transmission bandwidth ... [7] Br¨ ninghaus K and Rohling H., “On the duality of multi-carrier spread spectrum and single-carrier u transmission,” in Proc International Workshop on Multi-Carrier Spread- Spectrum (MC-SS’97), ... MT-CDMA, each sub-channel is broadband and more complex receivers are required 86 MC-CDMA and MC-DS-CDMA 2.2.2 Downlink Signal In the synchronous downlink, the signals of K users are superimposed...

Ngày tải lên: 09/08/2014, 19:22

... success and it is currently part of several high-rate wireless LAN standards, e.g., IEEE 802.11a/g/h, ETSI HIPERLAN/2, and MMAC, and is also part of the IEEE 802.16a and draft ETSIHIPERMAN WLL standards ... conversion and methods for modulating and demodulating a carrier with a complex OFDM time signal Multi-Carrier Modulation and Demodulation 121 Total channel bandwidth Useful bandwidth Guard band Unused ... Kaiser S., “Trade-off between channel coding and spreading in multi-carrier CDMA systems,” in Proc IEEE International Symposium on Spread Spectrum Techniques and Applications (ISSSTA’96), Mainz, Germany,...

Ngày tải lên: 09/08/2014, 19:22

... channel θn−n ,i−i and the variance of the noise σ In the mobile radio channel, it can be assumed that the delay power density spectrum ρ(τ ) and the Doppler power density spectrum S(fD ) are ... shown To evaluate and optimize the channel estimation, a multi-carrier reference scenario typical for mobile radio systems is defined The frequency band has a bandwidth of B = MHz and is located ... sequences The I and R sequences have the same length N1 , where in the I sequence (resp R sequence) the imaginary (resp real) components are and the real (resp imaginary) components are The I and R sequences...

Ngày tải lên: 09/08/2014, 19:22

... Performance of narrowband interference rejection with MC-CDMA 188 Implementation Issues These results show that the combination of spread spectrum with OFDM in the presence of multitone narrowband interference ... codes 4.7.3 Narrowband Interference Rejection in MC-CDMA The spread spectrum technique in combination with rake receivers is an interesting approach to remove the effects of interference and multipath ... transmitter consists of a spreader, transmit filter and the HPA The receiver is made out of the receive filter and the despreader, i.e., detector It should be noticed that the transmit and the receive filters...

Ngày tải lên: 09/08/2014, 19:22

... bandwidth and data rate, is expected to have a better acceptance Broadband Satellite Fourth Generation Platform Broadband WLAN HL2/802.11 S-UMTS Terrestrial Broadcast DVB-S DVB-T DAB Broadband ... environments, and mobility For high coverage areas with high delay spread, large spreading factors can be applied and for low coverage areas with low delay spread, the smallest spreading factor ... This broadband packet-based air interface applies variable spreading factor orthogonal frequency and code division multiplexing (VSF-OFCDM) with two-dimensional spreading in the downlink and MC-DS-CDMA...

Ngày tải lên: 09/08/2014, 19:22

... transmission capacity, and whether they Multi-Carrier and Spread Spectrum Systems K Fazel and S Kaiser  2003 John Wiley & Sons, Ltd ISBN: 0-470-84899-5 234 Additional Techniques for Capacity and Flexibility ... Atarashi H., Maeda N., Abeta S and Sawahashi M., Broadband packet wireless access based on VSFOFCDM and MC/DS-CDMA,” in Proc IEEE International Symposium on Personal, Indoor and Mobile Radio Communications ... [3] Atarashi H and Sawahashi M., “Variable spreading factor orthogonal frequency and code division multiplexing (VSF-OFCDM),” in Proc International Workshop on Multi-Carrier Spread- Spectrum & Related...

Ngày tải lên: 09/08/2014, 19:22

... It is expressed in bit/s/Hz/cell or sector Spreading: operation of enlarging/spreading the spectrum Several spreading codes can be used for spectrum spreading Synchronous: users transmitting following ... (STTC) 237–238 UMTS 253 Spatial diversity 233 Spreading codes 52–54 PAPR 54, 184–185 Spreading length 34, 49, 55, 201 Spread spectrum 30–45 Spread spectrum multi-carrier multiple access (SS-MC-MA) ... Frame: ensemble of data and pilot/reference symbols sent periodically in a given time interval, e.g., OFDM frame, MAC frame Multi-Carrier and Spread Spectrum Systems K Fazel and S Kaiser  2003 John...

Ngày tải lên: 09/08/2014, 19:22

... Networks Oy, Finland, 2001 [23] T H Stitz and M Renfors, “Filter bank based narrowband interference detection and suppression in spread spectrum systems,” in Proc IEEE Int Symp Circuits and Systems, ... the signals as they were before the first one (except for the scaling factor) Upsampling (spectral contraction) and recombining with the other ˆ ˆ subband signals yields I and Q, similar to I and ... of narrowband jamming and interference,” IEEE Trans Communications, vol 26, no 2, pp 209–216, 1978 [4] J W Ketchum and J G Proakis, “Adaptive algorithms for estimating and suppressing narrow-band...

Ngày tải lên: 23/06/2014, 01:20

... [31] In general, spread spectrum techniques are used for their robustness to narrowband interference and also to establish secure communications Compressed sensing by spread spectrum In this ... with a random waveform and randomly under-sample the result in time-domain The random convolution is performed through a random pre-modulation in the Fourier domain and the signal thus spreads ... Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques Gilles Puy∗1,2 , Pierre Vandergheynst1 , R´mi Gribonval3 and Yves Wiaux1,4,5...

Ngày tải lên: 20/06/2014, 20:20

... [31] In general, spread spectrum techniques are used for their robustness to narrowband interference and also to establish secure communications Compressed sensing by spread spectrum In this ... with a random waveform and randomly under-sample the result in time-domain The random convolution is performed through a random pre-modulation in the Fourier domain and the signal thus spreads ... Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques Gilles Puy∗1,2 , Pierre Vandergheynst1 , R´mi Gribonval3 and Yves Wiaux1,4,5...

Ngày tải lên: 21/06/2014, 17:20

... với FHSS Ví dụ Direct Sequence Spread Spectrum Transmitter Direct Sequence Spread Spectrum Transmitter Direct Sequence Spread Spectrum Using BPSK Example Approximate Spectrum of DSSS Signal Vấn ... khe thời gian dùng để truyền khung Trải phổ nhảy tần Frequency Hopping Spread Spectrum     Frequency Hopping Spread Spectrum (FHSS) Được phát minh nữ diễn viên Hollywood Hedy Lamarr, Là kĩ ... k chíp mã tương ứng với từ tần số Trải phổ dãy trực tiếp Direct Sequence Spread Spectrum    Direct Sequence Spread Spectrum (DSSS) Sử dụng mã trải phổ băng rộng để điều chế tín hiệu sóng mang...

Ngày tải lên: 13/09/2012, 11:16

... Reserved Narrowband vs Spread Spectrum Narrowband (High Peak Power) Power Spread Spectrum (Low Peak Power) Frequency February 2005 Copyright 2005 All Rights Reserved Narrow Band vs Spread Spectrum ... Sequence Spread Spectrum q Spread spectrum increases the bandwidth of the signal compared to narrow band by spreading the signal q There are two major types of spread spectrum techniques: FHSS and ... then de-spreads it into the original data bandwidth at the receive q Spread spectrum is characterized by: wide bandwidth and low power q Jamming and interference have less effect on Spread spectrum...

Ngày tải lên: 13/09/2012, 11:16

Ngày tải lên: 29/09/2013, 20:20

... transmissions in the unlicensed 2.4 GHz ISM-band, requiring spread spectrum modulation: DSSS (Direct Sequence Spread Spectrum) and FHSS (Frequency Hopping Spread Spectrum) Only the RF transmission has ... - discontinuous, narrowband - narrowband interference in the same channel is not reduced + narrowband interference in a different channel has no influence - some of the narrowband channels are ... Tx power is spread, this gives less interference reduction + continuous, broadband + narrowband interference in the same channel is reduced by the PG Multipath + rejection if the bandwith is wider...

Ngày tải lên: 13/12/2013, 00:15

... bps The Soneplex Broadband and Soneplex Loop Extender systems each use displays, 512 bits Status and command displays are supported TL1 Interface Transaction Language (TL1) commands may be used ... ports, the MPU and APU modules are the same for both the Soneplex Broadband and Soneplex Loop Extender systems Soneplex Loop Extender Chassis CRITICAL / MAJOR / MINOR PORT -48 V POWER AND HOUSEKEEPING ... alarm processor unit (APU) provides the critical, major and minor alarm indications and dry relay contacts for the Soneplex Broadband and Soneplex Loop Extender systems These alarms are available...

Ngày tải lên: 21/12/2013, 06:19

... (1-52), and the assumption that each of the has a spectrum confined to yields 1.1 BLOCK CODES where if 19 and otherwise, and Since the real and imaginary components of are jointly Gaussian, this random ... Frequency-Hopping Systems 3.1 Concepts and Characteristics 3.2 Modulations MFSK Soft-Decision Decoding Narrowband Jamming Signals Other Modulations Hybrid Systems 3.3 Codes for Partial-Band Interference Reed-Solomon ... Gaussian random variable Straightforward calculations using (1-40) and the confined spectra of the indicates that the real and are imaginary components of are uncorrelated and, hence, independent and...

Ngày tải lên: 20/01/2014, 06:20