It is well known that DC offset degrades the performance of analog adaptive filters. The effects of DC offset on LMS derivatives such as sign-data LMS, sign-error LMS and sign-sign LMS have been studied to much extent but that on MLMS, VSSLMS and NLMS algorithms have remained relatively ignored. The present paper reports the effects of dc offset on LMS algorithm and its four variations Sign LMS...

Stator flux oriented vector control of induction motor (IM) drives for speed sensorless control has several advantages. But the application of a pure integrator for the flux estimation is difficult due to the presence of measurement noise and dc offset. To overcome these problems, some have used a programmable cascaded low pass filter (PCLPF). In this paper, it is shown that some problems still...

Vdd Vdd Vdd A floating-gate pseudo-differential transconductor is presented, in which the differential input signal is allowed to have a dc offset. Normally such an offset would render a normal CMOS differential pair useless. The circuit "VX v y " inherently removes any dc offset from the floating gates lout(-) lO"I(+) by feedback mechanisms involving Fowler-Nordheim electron tunneling and hot-...

This paper describes how to perform a low complexity frequency offset estimation in the presence of direct current (DC) offset based on a received periodic preamble. By designing a suitable preamble, we perform frequency and DC offsets estimation concurrently, followed by a simple compensator which reduces the frequency offset error induced by the presence of either a residual or actual DC offs...

DC-offset and DC-suppression are key parameters in bioelectric amplifiers. However, specific DC analyses are not often explained. Several factors influence the DC-budget: the programmable gain, the programmable cut-off frequencies for high pass filtering and, the low cut-off values and the capacitor blocking issues involved. A new intermediate stage is proposed to address the DC problem entirel...

The cancellation of DC-offsets and 2-order-type RF-self-mixing products (RFS2) is presented for six-port-based, analog direct receiver front-ends. It is shown that the signal dependent RFS2 comprising a dynamic DC-offset as well as the front-end dependent static DC-offset are generated systematically and not only by spurious effects unlike conventional, mixer-based front-ends. Due to this fact,...

sensorless speed torque control of induction machines has been widely used in many industrial applications. the simple method of direct vector control can provide tacholess control as well as more complex approaches. in this method, the motor flux can be obtained by measuring voltage and current and integrating motor back electromotive force. the only required motor parameter is stator resistan...

A compacted and low-offset low-power CMOS amplifier for biosensor application is presented in this paper. It includes a low offset Op-Amp and a high precision current reference. With a novel continuoustime DC offset rejection scheme, the IC achieves lower offset voltage and lower power consumption compared to previous designs. This configuration rejects large DC offset and drift that exist at t...