| 摘要 |
<p>Error coding uses at least two generating polynomials to provide different degrees of error protection and to optionally superimpose a phantom channel on a primary channel, without the need for explicit signaling from transmitter to receiver. An encoded message is CRC decoded at the receiver with at least two different generating polynomials. Based on the decoding results, it is determined which of the polynomials was used to encode the message. For instance, if one generating polynomial was used, this may indicate that a second channel has been superimposed onto the primary channel and that second channel may be extracted. If another polynomial was used, this indicates that no second channel has been superimposed. In essence, the receiver deduces the transmitter's choice of CRC generating code, the degree of redundancy and/or presence of the second channel by analyzing the incoming bit stream rather than relying on explicit signaling.</p> |
