초록 ▼

A method and apparatus for determining the transmission format of complex symbols in a received signal which is formatted in complex symbol blocks. Each block has a first occurrence (GI.sub.k) of a sequence of complex symbols and second occurrence (gI.sub.k) of the same sequence of complex symbols.

A method and apparatus for determining the transmission format of complex symbols in a received signal which is formatted in complex symbol blocks. Each block has a first occurrence (GI.sub.k) of a sequence of complex symbols and second occurrence (gI.sub.k) of the same sequence of complex symbols. A correlation between the first and second occurrences is effected by means of acquisition and correlation time windows, the transmission format being determined by searching for maximum correlation between the first complex symbol sequence and the second complex symbol sequence via synchronization of the windows with the received signal so that the windows select the first occurrence and the second occurrence of complex symbols, respectively. Particularly useful in a digital transmission system employing Orthogonal Frequency Division Multiplexing (OFDM).

대표청구항 ▼

[ What is claimed is:] [1.]1. A method of determining a transmission format for complex symbols in a signal formatted in complex symbol blocks, each block having a first occurrence of a group of complex symbols and a second occurrence of the same group of complex symbols, the two occurrences having

[ What is claimed is:] [1.]1. A method of determining a transmission format for complex symbols in a signal formatted in complex symbol blocks, each block having a first occurrence of a group of complex symbols and a second occurrence of the same group of complex symbols, the two occurrences having a like duration, the method effecting a correlation between the first occurrence and the second occurrence for determining characteristic features of the transmission format, characterized in that the method comprises the following steps:storing a first sequence of complex symbols taken from a received signal via an acquisition time window which has a longer duration than the duration of the occurrences of complex symbols,correlating the first sequence of complex symbols with a second sequence of complex symbols selected at another moment in the received signal, via a correlation time window which has a duration equal to that of the acquisition time window, anddetermining characteristics of the transmission format by searching for maximum correlation between the first and the second sequences of complex symbols by synchronizing the acquisition window with the received signal and by positioning the acquisition time window and the correlation time window relative to each other in time, the maximum correlation appearing when the first and second sequences of complex symbols include said first and second occurrences, respectively.