IIIE   20352
INSTITUTO DE INVESTIGACIONES EN INGENIERIA ELECTRICA "ALFREDO DESAGES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Carrier Frequency Offset Estimation for OFDM-Based Cooperative Communications Systems
Autor/es:
MERCEDES PUZIO; GUSTAVO GONZÁLEZ; FERNANDO GREGORIO; JUAN E. COUSSEAU
Lugar:
Oro Verde, Provincia de Entre Ríos
Reunión:
Congreso; XIV Reunión de Trabajo en Procesamiento de la Información y Control (RPIC 2011); 2011
Institución organizadora:
Facultad de Ingenería, Universidad Nacional de Entre Ríos
Resumen:
We analyze in this work the carrier frequency offset (CFO) estimation issue of OFDM-based cooperative communications systems. We focus on the relaying phase of this scenario, where one or more relaying nodes decode and forward data, originated by a source node, to a single destination node. For an OFDM symbol to be decoded correctly, all its subcarriers must be orthogonal. If any relay node introduce a frequency offset in the assigned subcarriers subset, orthogonality is lost in the whole symbol and data cannot be recovered. A recently proposed training sequence, which consits of one OFDM block with a tile structure and a number of nulled subcarriers, is studied here. By using this subcarrier arrange ment, CFO can be estimated with conventional subspace-based methods, such as ESPRIT and MUSIC. In particular, the later achieves a better performance over a wider range of SNR. Despite their low computational complexity, these techniques evidence a high sensitivity to eigenvalue spread, which can be the subject of a future work.