Abstract: An interactive voice response system includes a server and a set of mobile clients. The server and clients include RF transceivers for exchanging messages over an RF channel. Each mobile client includes a microphone, a speaker or headset, a processor and a voice browser. The voice browser interprets voice pages received from the server. Upon receiving a particular voice page from the server, the voice browser outputs via the speaker voice prompts specified by the voice page. A speech recognition engine used by the voice browser converts voice responses from a user into a text response. The voice browser then performs an action based on the text response. The action taken may be to request a new voice page from the server, or to continue to interpret the current voice page.

Abstract: A reconfigurable lattice filter is employed to permit the same circuitry to function as a speech synthesizer and as a speech analyzer or recognizer. The lattice filter can be configured both as an all-pole filter (for synthesis) and as an all-zero filter (for analysis), with the choice being determined by the state of an analysis/synthesis signal (i.e., mode control signal) provided thereto. The connections between various elements in the circuitry are controlled by the analysis/synthesis signal, also.In synthesis mode, partial correlation coefficients are supplied to the filter from a microprocessor. The filter is excited by a one of a number of stored patterns simulating a glottal pulse for voiced sounds and by a pseudo-random noise generator for unvoiced sounds.In analysis mode, appropriate feedback control paths are enabled so as to provide to the filter coefficients which change in response to changes in the input speech waveform.