Communication device

A communication device, comprising:

• a connector connected a communication cable having multiple pairs of signal lines for transmitting a differential signal;
• and
• a plurality of pairs of transmission lines for transmitting the differential signal inputted/outputted through the connector,
• wherein a number of the pairs of the transmission lines is N (N is an even number), each pair of the transmission lines comprises (N−1) stages of sub-transmission lines generating a same amount of crosstalk as that caused at the connector, and (N−1) stages of connecting portions comprise a first stage connecting portion to connect a transmission path of the connector and a first stage sub-transmission line by a straight/cross connection, and second to (N−1) th stage connecting portions to connect an i (i=1 to N−2) th stage sub-transmission line and an (i+1) th stage sub-transmission line by the straight/cross connection, and
• wherein each pair of the transmission lines is different in all pairs in a number of the connecting portion having the cross connection, and as a j (j=an integer by 1 to N/2) th stage connecting portion in any one pair of the transmission lines has cross connection, a (N−j) th stage connecting portion in the any one pair of the transmission lines also has cross connection.