US 6,208,695 B1 · Method for reception of multicarrier signals and related apparatus

Abstract

A problem in the reception of terrestrially transmitted digital multicarrier broadcast signals is synchronization in case a receiver is switched on or tuned to another channel. The time required by the receiver to reach a given tuning frequency with adequate accuracy and to determine that the currently received signal is not a system-compliant signal is reduced significantly if a characteristic value calculated from correlation values between a windowed and FFT transformed section of the received signal and a reference symbol stored in the receiver does not exceed a pre-defined threshold. In such case the receiver can go ahead to the next tuning frequency. If, however, the characteristic value exceeds that threshold, then a system-compliant signal is found, even with an offset. The multicarrier signal will be further decoded in the normal way. Such conformity check can also be carried out in the subsequent normal reception mode.

Claims16

Dependent claims

A method for the reception of multicarrier signals which are arranged in frames with a synchronisation signal and at least one reference symbol per frame, comprising the steps of:

performing a frequency scanning or signal searching process;
detecting the synchronisation signal;
estimating a reference symbol time window position and computing an FFT using said reference symbol time window position;
demodulating the FFT output signal and carrying out within a frequency section, which preferably is shorter than the length of said FFT, a correlation using a generic reference symbol stored in the receiver;
calculating a characteristic value from correlation step values;
determining the multicarrier signal as being a system-conform signal if said characteristic value exceeds a pre-defined threshold and in such case further decoding said multicarrier signal;
and
determining the multicarrier signal as being not a system-conform signal if said characteristic value does not exceed said pre-defined threshold and in such case starting again or continuing said scanning or searching process.

5 more elements

Apparatus for the reception of multicarrier signals which are arranged in frames with a synchronisation signal and at least one reference symbol per frame, the apparatus comprising:

means for performing a frequency scanning or signal searching process;
means for detecting the synchronisation signal;
means for estimating a reference symbol time window position and for computing a FFT using said reference symbol time window position;
means for demodulating the FFT output signal and means for carrying out within a section, which preferably is shorter than the length of said FFT, a correlation using a generic reference symbol stored in the receiver;
and
means for calculating a characteristic value from correlation step values and for determining the multicarrier signal as being a system-conform signal if said characteristic value exceeds a pre-defined threshold and then further decoding said multicarrier signal, and for determining the multicarrier signal as being not a system-conform signal if said characteristic value does not exceed said pre-defined threshold and then starting again or continuing said scanning or searching process in said means for performing a frequency scanning or signal searching process.

3 more elements

Dependencies are inferred from the claim text.

Method for reception of multicarrier signals and related apparatus

Life of this patent

Method for reception of multicarrier signals and related apparatus

Life of this patent

Abstract

Claims16