Trainline system using an electromagnetic communication link

Claim 1

A communication link for permitting communications between adjacent cars of a multi-car vehicle, said link comprising: on at least a first one of said cars, a first multiplexing/demultiplexing means for: (A) (i) multiplexing first digital signals representative of the status or control signals of various systems on said first one of said cars, and for processing said first digital signals into a first digital trainline signal; (ii) first means for converting said first digital trainline signal to a first radio frequency signal; (iii) a first antenna mounted on one end of said first one of said cars for transmitting said first radio frequency signal; (iv) said first multiplexing/demultiplexing means converting a second radio frequency signal into a second digital trainline signal to provide second digital signals representative of the status or control signals of various systems on a second one of said cars; (v) said first antenna receiving said second radio frequency signal; said second one of said cars including a second multiplexer/demultiplexer means for: (B) (i) multiplexing said second digital signals, and for processing said second digital signals into a second digital trainline signal; (ii) second means for converting said second digital trainline signal to a second radio frequency signal; (iii) a second antenna mounted on said second one of said cars at an end thereof adjacent the end of the first car on which said first antenna is mounted, said second antenna transmitting said second radio frequency signal; (iv) said second multiplexing/demultiplexing means converting said first radio frequency signal into a first digital trainline signal to provide first digital signals representative of the status or control signals of various systems on said first one of said cars; (v) said second antenna receiving said first radio frequency signals; whereby communications can be sent from said first one of said cars to said second one of said cars and from said second one of said cars to said first one of said cars via said first and second antennae by free space radio frequency coupling; a first housing mounted on said first one of said cars for housing said first antenna; a second housing mounted on said second one of said cars for housing said second antenna; said first housing including a first shielding means surrounding said first antenna; said second housing including a second shielding means surrounding said second antenna; said first housing and said second housing each comprising an open end; said first and second housings being mounted such that the open end of the first housing faces the open end of the second housing.