System and method for analysis of the upper airway and a respiratory pressure support system

A system for analysis of the upper airway has a sensor arrangement with at least two sensor positions provided along a flow path leading to the mouth and/or nose of a user (4). A relation is derived between sensor signals at the two locations, and this is interpreted to detect at least the presence of upper airway obstructions, and preferably also the location and/or extent of such obstructions. The system is adapted to distinguish between inhalation and exhalation using the acoustic arrangement signals at the first and second locations.