摘要:
The invention relates to a method for determining the arrival time of a UWB pulse at a receiver. When the pulse is modulated at an RF frequency, the receiver comprises: a quadrature demodulator (330); a first correlation stage (351, 352) for correlating the signal in phase with the first and second signals of an orthogonal base over a time window and a second correlation stage (353, 354) for correlating the signal in quadrature with the first and second signals of the orthogonal base over the same window; a phase estimator (360) that estimates the phase of the signal received in the orthogonal base on the basis of the correlation results from the first and/or second correlation stage(s); and computing means (370) for determining the arrival time on the basis of the estimated phase.
摘要:
Des satellites fixes (Si) émettent des signaux de synchronisation, mutuellement temporellement asynchrones. Un dispositif récepteur fixe (DR) reçoit ces signaux de synchronisation (SSYi) au même titre que le dispositif mobile (DM). Comme les signaux de synchronisation émis par les satellites ne sont pas temporellement synchronisés entre eux, le dispositif récepteur fixe va transmettre des informations temporelles manquantes (INFT) au dispositif mobile, élaborées à partir de la réception par le dispositif fixe de ces signaux de synchronisation, afin que le dispositif mobile puisse déterminer sa position. A l'inverse, si le dispositif récepteur fixe, ou bien une entité couplée au dispositif fixe, souhaite déterminer la position du dispositif mobile, c'est le dispositif mobile qui va transmettre au dispositif fixe les informations temporelles manquantes qui vont permettre au dispositif fixe ou à l'entité, de déterminer la position du dispositif mobile.
摘要:
A method is disclosed for deriving an estimation value of a clock-error (E) for a slave clock (3), wherein the slave clock (3) is set at a nominal slave period (TLCLK_n) and outputs a sequence of slave clock signals (3') at an actual slave period (TLCLK) and wherein the difference between the actual slave period (TLCLK) and the nominal slave period (TLCLK_n) is approximated by the estimation value of the clock-error (E). The method includes: - receiving a sequence of master clock signals (5') at a master period (THCLK) that is output from a master clock (5), and a sequence of slave clock signals (3') at an actual slave period (TLCLK) that is output from the slave clock (3), - providing a measurement time period (43) that begins at a starting time point (43_s) and ends at an ending time point (43_e), wherein the measurement time period (43) includes a common multiple time period, the common multiple time period ends at the ending time point (43_e) and has a length in time that is a first multiple (n) of the nominal slave period (TLCLK_n) and is a second multiple (m) of the master period (THCLK), - providing a sequence of storing time points (43_i) temporally displaced within the common multiple time period by the actual slave period (TLCLK), the last of the storing time points being the ending time point (43_e) of the measurement time period (43), - starting to count the slave signals (3') and the master signals (5') at the starting time point (43_s), - for more than one storing time point (43_i), storing a master count value that represents the counted master signals (5') in association with the respective storing time point (43_i), - deriving an actual master count sum value by adding the stored master count values, - deriving, for the more than one storing time points, a nominal master count sum value, and - deriving the estimation of the clock-error (E) for the slave clock (3) by relating the actual master count sum value to the nominal count sum value.
摘要:
The invention concerns a multi-channel pulsed UWB receiver (400). The receiver comprises a first stage (420) for translating the received signal to a baseband or intermediate frequency, a second stage (430) performing a quadrature mixing on the in-phase and quadrature channels of the first stage, a third stage (440) performing an integration, over a time window, of the signals from the second stage, and a fourth stage (450) combining the results of the integration of the third stage in order to provide the real part and the imaginary part of the modulation symbol. The receiver can be configured (figures 4A-4H) depending on the receiving channel and the type of treatment selected.