A Wideband CMOS Low Noise Amplifier Employing Noise and IM2 Distortion Cancellation for a Digital TV Tuner

Abstract

A wideband CMOS low noise amplifier (LNA) with single-ended input and output employing noise and IM2 distortion cancellation for a digital terrestrial and cable TV tuner is presented. By adopting a noise canceling structure combining a common source amplifier and a common gate amplifier by current amplification, the LNA obtains a low noise figure and high IIP3. IIP2 as well as IIP3 of the LNA is important in broadband systems, especially digital terrestrial and cable TV applications. Accordingly, in order to overcome the poor IIP2 performance of conventional LNAs with single-ended input and output and avoid the use of external and bulky passive transformers along with high sensitivity, an IM2 distortion cancellation technique exploiting the complementary RF performance of NMOS and PMOS while retaining thermal noise canceling is adopted in the LNA. The proposed LNA is implemented in a 0.18 m CMOS process and achieves a power gain of 14 dB, an average noise figure of 3 dB, an IIP3 of 3 dBm, an IIP2 of 44 dBm at maximum gain, and S11 of under 9 dB in a frequency range from 50 MHz to 880 MHz.The power consumption is 34.8 mW at 2.2 V and the chip area is 0.16 mm 2 .

Exploiting cross-coupled and body-driven techniques for noise cancellation of an inductor-less wideband LNA

“…The noise contribution of transistors MN 1 at differential output nodes is: (15) in which 2 1 ,MN n i denotes the thermal noise of transistor MN 1 . Due to the symmetry of the circuit, coefficient 2 appears in (15).…”

A 3–6 GHz Current Reused Noise Canceling Low Noise Amplifier for WLAN and WPAN Applications

“…However, because of large interferences in communication systems, the highly linear, high gain, and low noise figure LNA is desired [22]. There are some linearization techniques such as: feed forwarding [23]; in which, the cancellation of second intermodulation (IM2) and third intermodulation (IM3) terms cannot be done simultaneously, IM2 injection [24], postdistortion (PD) [25], derivative superposition (DS) (including conventional, complementary, and modified DS) [26], and etc. Actually, derivative superposition (DS) is one special case of the feed forward technique.…”

A 1.1 V 6.2 mW, wideband RF front-end for 0 dBm blocker tolerant receivers in 90 nm CMOS

“…Another advantage of this inverter-like architecture is its improved linearity. The complementary characteristics of the NMOS and PMOS transistors can be utilized for cancelling the first and second derivative of g m (g 0 m and g 00 m ) in a wide range of input voltages [7,11,12]. As our objective is to utilize a large part of the available voltage headroom for our signal, this is essential.…”