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This paper presents the receiver model for T-DMB location AEAS based on TII(Transmitter Identification Information). T-DMB has been well considered on the carrier for AEAS(Automatic Emergency Alert Service) broadcasting. Our receiver model estimates the geographical location of the receiver using TII symbol after checking EWS(Emergency Warning Service) data field periodically. Then AEAS message can be displayed on only receivers that are located at the alert region or the neighboring region. In our experiment, we verified that our model can provide AEAS message to all DMB terminals but display AEAS message on only DMB terminals that are located at the alert region.

When convolution code is used in wireless coded orthogonal frequency division multiplexing (COFDM) systems, effective maximum likelihood (ML) decoding requires information on the frequency response of each subcarrier. This translates into increased hardware complexity, for instance, in the form of an additional deinterleaving block. We propose an optimal weighting scheme that combines the metrics for soft decision and channel influence into a single metric, can be performed before the deinterleaving block, and makes ML decoding possible. It shows comparable performance to ML decoding and better performance over suboptimal decoders.

An OFDM signal with large peak-to-average power ratio (PAPR) can cause power degradation (inband distortion) and spectral spreading (out-of-band radiation) by being clipped passing through a power amplifier. The PAPR characteristics are analyzed in two different aspects. From the foundation of the analysis, we propose Hadamard transform, which is ascribed to the relationship between the autocorrelation function and PAPR. Extensive computer simulations show that Hadamard transform is an effective technique to reduce PAPR.