Communication device, communication method, and communication program

A communication device comprising:

• circuitry configured to
• receive data through a free-space optical communication;
• detect an interleaving length of the received data;
• and
• deinterleave the received data based on the detected interleaving length,
• wherein
• the interleaving length is based on information on a transmission characteristic of the free-space optical communication used for transmitting the data,
• the interleaving length is changeable,
• the circuitry is configured to shape the interleaved data based on a data format configured to make the interleaving length detectable on a receiving side of the free-space optical communication,
• the data format is such that the data includes synchronization codes,
• the circuitry is configured to dispose at least two types of the synchronization codes in the data so as to make the interleaving length detectable on the receiving side of the free-space optical communication, and
• the at least two types of the synchronization codes includes:
• a first synchronization code representing a start point or an end point of the interleaving, and
• a second synchronization code representing a continuation point of the interleaving at intervals of a predetermined data length based on the determined interleaving length.

A communication method performed by a communication device including a processor, the method comprising:

• based on information on a transmission characteristic of a free-space optical communication used for transmitting data, determining an interleaving length of the data;
• interleaving the data based on the determined interleaving length;
• and
• transmitting the interleaved data,
• wherein
• the interleaving length is changeable,
• the circuitry is configured to shape the interleaved data based on a data format configured to make the interleaving length detectable on a receiving side of the free-space optical communication,
• the data format is such that the data includes synchronization codes,
• the circuitry is configured to dispose at least two types of the synchronization codes in the data so as to make the interleaving length detectable on the receiving side of the free-space optical communication, and
• the at least two types of the synchronization codes includes:
• a first synchronization code representing a start point or an end point of the interleaving, and
• a second synchronization code representing a continuation point of the interleaving at intervals of a predetermined data length based on the determined interleaving length.