| 摘要 |
<p>Described herein is a SAW-less wireless transmitter arrangement (500) that does not suffer from the problem of out-of-band noise. An active filter/amplifier arrangement (520) filters/amplifies an input signal from a digital-to-analogue converter (505) and provides an input to a variable passive filter arrangement (530) that forms a passive pole arrangement with a capacitance element (568). The variable passive filter arrangement (530) comprises an array of switchable resistance elements (532, 536, 538, 542, 544, 546, 550, 554, 556, 558, 560, 562, 564). Feedback loops (570, 575, 580, 585, 590, 595) are provided from the passive filter arrangement (530) to the active filter/amplifier arrangement (520), each feedback loop also including a switchable resistance element (571, 576, 581, 586, 591, 596). Selective switching of the resistance elements (532, 536, 538, 542, 544, 546, 550, 554, 556, 558, 560, 562, 564) in the array and those in the associated feedback loops (571, 576, 581, 586, 591, 596) provides a transmitter which both compensates for out-of-band noise and non-linearity in the resistance elements (532, 536, 538, 542, 544, 546, 550, 554, 556, 558, 560,562,564).</p> |
