NTU Amps Up Mobile Sound Quality
Summary
During development, the NTU team used Brüel & Kjær’s PULSE system and Head and Torso Simulator (HATS) to ‘listen’ to the sound from a headset driven by a CDA and then measure the acoustical audio signal.The pinhead-sized chip encompassing the novel CDA design ultimately means that the audio from smartphones will sound like it is coming from high-end stereos, while wireless headphone users will be able to enjoy a longer battery life.However, in practice, CDAs have imperfections that generate distortion and noise.To obtain high power efficiency without resorting to a high switching frequency, the team at NTU proposed a novel CDA design, which embodies an input-modulated carrier generator and a phase-error-free, pulse-width modulation (PWM) modulator.During development, the NTU team used Brüel & Kjær’s PULSE system and Head and Torso Simulator (HATS) to ‘listen’ to the sound from a headset driven by a CDA and then measure the acoustical audio signal.NTU senior research scientist Ge Tong explained: “This was essentially an integrated circuit design project.The pinhead-sized chip encompassing the novel CDA design ultimately means that the audio from smartphones will sound like it is coming from high-end stereos, while wireless headphone users will be able to enjoy a longer battery life.Free online training courses, conducted by our expert engineers, run throughout the year too.Brüel & Kjær is a subsidiary of UK-based Spectris plc, which has annual sales of £1.1bn and employs around 8,300 people worldwide across its four business segments.