A navigation system using Visible Light Communications (VLC), the associated transmitters and receivers, the navigation system comprising a plurality of VLC transmitters (201 to 207) and one or more GNSS receiver (430), each of the VLC transmitters being configured to transmit a positioning signal comprising a navigation message including time information, where the time information is a transmission time of a specific part of said navigation message derived from a GNSS reference time. The receivers (221) according to the invention are configured to calculate a position from either VLC pseudo ranges, GNSS pseudo ranges, or a combination thereof.
The associated methods for transmitting positioning signals in a navigation system according to the invention, and for determining a position from a plurality of positioning signals transmitted by said navigation system.