SOFT DECODING OF BCH CODES APPLIED TO MULTILEVEL MODULATION CODES FOR RAYLEIGH FADING CHANNELS

  • Buda F.
  • Fang J.
  • Sehier P.

8PSK multilevel codes (MLC) designed for fading channels with multistage decoding (MSD) are reported in this paper. Binary block BCH codes of medium length have been chosen to construct powerful MLC 8PSK schemes and an efficient soft decision decoding algorithm has been used in the MSD decoder. Error rate performances ...

A PRAGMATIC RAKE RECEIVER FOR DIRECT SEQUENCE SPREAD SPECTRUM CODED TROPOSCATTER TRANSMISSIONS

  • Sehier P.
  • Vivier G

For tactical troposcatter transmissions, explicit diversity techniques (such as spatial, angular or frequency diversity) are not usable due to severe constraints on equipment size and cost. Multipath fading can be efficiently overcome by using implicit diversity techniques such as spread spectrum where the use of a signal bandwidth much wider ...

A NEAR OPTIMUM DIVERSITY COMBINING METHOD ADAPTED TO SLOW FREQUENCY HOPPING DPSK TRANSMISSION

  • Buda F.
  • Sehier P.
  • Vivier G

Frequency hopping (FH) is used in communication systems to mitigate interference such as jamming. For low data rate, fast FH and MFSK are often used in combination with diversity, which consists in transmitting every symbol on several hops. It brings additional protection. Several robust diversity combining methods have been developed ...

REDUCED COMPLEXITY FREQUENCY ESTIMATOR APPLIED TO BURST TRANSMISSION

  • Bergogne C
  • Sehier P.

In burst transmission, carrier recovery is a crucial point for synchronization systems. Indeed, an imprecise frequency estimation can cause cycle slips. An unbiased feedforward frequency estimator, for M-PSK modulated signals, in the non data aided mode (NDA) is derived from the maximum likelihood (ML) principle. A compromise is realized between ...

A NEW JAMMER ESTIMATION METHOD ADAPTED TO FH-PSK WAVEFORMS

  • Aubry I
  • Brelivet P
  • Sehier P.

It is well known that channel state information (CSI) can be used by the receiver to improve the BER performance of coded spread spectrum communications. Unfortunately, this information is generally not available, and has to be estimated by the receiver. The paper presents an efficient method for estimating jammer parameters, ...

A CONCATENATED CODING SYSTEM WITH 3 CODES

  • Fang J.
  • Sehier P.

A concatenated coding scheme with 3 codes is studied. A product code is used for the outer code, and the super channel including the inner code with Viterbi decoding is supposed bursty. An array decoding procedure for the outer code that incorporates error detection and erasure decoding is presented, and ...

CRYOGENIC LOAD CALCULATION OF HIGH TC CURRENT LEAD

  • Cottevieille C.
  • Herrmann P-F
  • Leriche A.
  • Verhaeghe T

EUROPEAN PROJECT FOR THE DEVELOPMENT OF HIGH TC CURRENT LEADS

  • Cottevieille C.
  • Herrmann P-F
  • Leriche A.
  • Verhaeghe T

A NEW CLASS OF AC SUPERCONDUCTING CONDUCTORS

  • Estop P
  • Verhaeghe T
  • Weber W.

HIGH PERFORMANCE SEMICONDUCTOR OPTICAL PREAMPLIFIER

  • Doussiere P.
  • Garabedian G
  • Graver C.
  • Leclerc D.