Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Confusion
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Ramp
General None Reported / Taken
Airport; Chart Or Publication; Procedure
We were told to taxi by tower after landing on [Runway] 10L and contact Ramp Control. When we contacted Ramp Control they said we had entered the ramp without clearance; but we were still on a designated taxiway. My First Officer and I tried to find out exactly what is considered 'the ramp' on any of the charts or airport pages; but could not find any description of what is actually 'a ramp' or 'a taxiway' anywhere. We looked for signs on the way out but there weren't any. There were some alternating double-dashed lines in FLL around what I would consider 'the ramp' that were about 100 yards off the various concourses; but we were nowhere near those when we taxied in. One factor in this whole thing is the FO contacted the Ramp control frequency on the 10-9 page for North Ramp but only South Ramp was open. But we still were not in or on the ramp when we got that mess sorted out.
Air carrier Captain reported a ramp incursion and cited as contributing factors a lack of clear markings; signage and charting to designate the ramp area at FLL airport.