Communication device having cross-platform communication function, communication system having the same and communication method thereof

A communication system having cross-platform communication function, comprising:

• a plurality of communication devices;
• a plurality of mobile devices corresponding to the communication devices respectively;
• and
• a cloud processing system configured to communicate with the mobile devices;
• wherein any one of the communication devices is configured to obtain a coordinate of a current location thereof to generate a location information of the communication device, and transmit the location information to the mobile device corresponding thereto and a nearby mobile device close to the mobile device, whereby the location information is transmitted to the cloud processing system via the mobile device and/or the nearby mobile device, wherein when any one of the communication devices loses contact, the cloud processing system is configured to calculate a location of the communication device losing contact according to a moving trajectory, a moving speed, hardware errors and last several pieces of the location information of the communication device losing contact, and a corresponding location information of the communication device adjacent to the communication device losing contact.