Abstract: A voice communications device (4) and speech processing method are described. A speech signal, generated by a microphone (41) in response to speech input (2) in to the microphone (41) by a user (1), has a proportion extracted therefrom. The speech signal is transmitted to an appliction apparatus that may be integral or remote. A speech quality value is evaluated for the extracted speech signal. An indication of the quality of the speech signal, based on the speech quality value, is indicated to the user. Thus a direct indication of the current quality of a received speech signal, in a form that is easily interpreted by a non-expert user of the device, is provided, thereby providing the use with an opportunity to improve the sppech quality. Examples of appliction apparatus include hands-free telephones and automatic speech recognition systems.

Abstract: A catheter tracking system for locating and tracking a catheter head 16 with reference to a part of the human or animal body 1 includes a catheter having a catheter head which is arranged to be conveyed through the human or animal body to a desired location and a plurality of spaced apart transducers at least one of which is disposed on the catheter. At least two further transducers are disposed at predetermined reference positions in and/or around the human or animal body. A signal processing unit operates to energize the plurality of transducers, and in accordance with a time of flight of signals between the reference transducers and the transducer disposed on the catheter, to determine the location of the catheter head with respect to the reference transducers. The energized signals consist of predetermined waveforms which when analyzed by the signal processing unit serve to increase an accuracy with which the catheter head location is determined.

Abstract: A catheter tracking system as depicted in FIGS. 1,2, and 3 for locating and tracking a position of a catheter head 16 within a part of a human or animal body 1. The catheter tracking system including of a catheter 10 having a head 16 which is arranged to be conveyed through a human or animal body to a desired location, a plurality of magnetic field transducers, at least one of which is disposed on the catheter 18, and others of which are located in/or around a body and which serve as reference transducers 19, and a control unit which energises the plurality of magnetic field transducers. Upon processing of the magnetic field signals the position of a catheter head 16 with respect to reference transducers 19 is determined.

Abstract: A catheter localization system for determining a position of a catheter (1, 2) within a part of the human or animal body (3), comprising at least one catheter (1, 2) having a plurality of acoustic transducers (6) disposed on the catheter in a spaced apart relationship. Each acoustic transducer (6) is arranged to transmit or receive acoustic signals (12, 14). A signal processing unit (8) is coupled to the plurality of acoustic transducers (6) and arranged to selectively energize the transducers (6) and consequent upon acoustic signals (12, 14) received by the acoustic transducers (6) generate a plurality of acoustic transfer functions (24, 28) representative of an effect of the part of the body on the acoustic signals, which signal processing unit (8) further operates to generate data appertaining to a three dimensional representation (36) of the part (4) of the human body (3) in accordance with the plurality of transfer functions.