Because of crystal oscillator error,inter-symbol interference and baseline drift in industrial optical fiber communication,the optical fiber receiver has the problem of high error rate of data recovery. In long-distance industrial communication,the electrical level jitter of serial data at the receiver will increase. To solve this problem,a method of clock and data recovery for long-distance industrial optical fiber communication was proposed. Six-times frequency clock was used for sampling. The rising or falling edge of serial data can be determined and collected under the same clock,which can select dynamical sampling clock. According to the electrical level jitter tolerance,the validity of the sampled data under different conditions can be verified. After data processing,the six-times sampled data was restored to serial data under the local clock,which is finally converted to the parallel data. Simulation and test verified the effectiveness of the proposed method.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |