TXD_W2_PLCP_SIGNAL
rt2x00_set_field32(&word, TXD_W2_PLCP_SIGNAL, txdesc->u.plcp.signal);
rt2x00_set_field32(&word, TXD_W2_PLCP_SIGNAL, txdesc->u.plcp.signal);
rt2x00_set_field32(&word, TXD_W2_PLCP_SIGNAL, txdesc->u.plcp.signal);