An ion mobility spectrometer includes a plurality of substrates defining a measurement region for receiving a singular laminar gas flow without any carrier or sheath gas. The measurement region includes an ionization region that is continuous with a detection region. An ionizing electrode, which may include a plurality of asymmetric electrodes, produces ions in the gas sample within the ionization region. The ionizing electrode may apply a time varying voltage to the gas sample to generate a time dependent ion production. A field generating electrode generates an electric field to deflect the ions in the gas sample, and a detection electrode array detects the deflected ions within the detection region. A controller is configured to determine ion species based on the detection of ions by the detection electrode array. The detection electrode array may include a plurality of detection electrodes, and the controller may be configured to differentiate ion species based on which ions are detected by which one of the detection electrodes.