Mode detection for DVB receiver

A method for detecting a symbol length of a received signal, the method comprising:

• detecting the symbol length of the received signal by correlating, using correlation circuitry, the received signal with first and second versions of the received signal to output respective first and second correlation signals and a control signal identifying the detected symbol length, wherein the control signal is generated based on a weighted function of a first type of characteristic and a second type of characteristic of the first and second correlation signals, and wherein the correlating comprises multiplying the received signal with the first and second versions of the received signal;
• receiving, with selection circuitry, the control signal and each one of the first and second correlation signals;
• and
• filtering, using filter circuitry, a selected one of the first and second correlation signals to create a plurality of filtered correlation signals, wherein the selected one of the first and second correlation signals is selected based upon the received control signal.

A system for detecting a symbol length of a received signal, the system comprising:

• a plurality of correlators, wherein each correlator is operable to correlate the received signal with a time-delayed version of the received signal to output a correlated signal, and wherein each correlator multiplies the received signal with the time-delayed version of the received signal;
• first decision circuitry coupled to the plurality of correlators and operable to detect the symbol length from the correlated signals and output a control signal identifying the detected symbol length, wherein the control signal is generated based on a weighted function of a first type of characteristic and a second type of characteristic of each of the correlated signals;
• and
• selector circuitry coupled to the plurality of correlators and operable to select one of the correlated signals received from the plurality of correlators based upon the received control signal.