A new physical, compact and continuous Model for extremely Scaled MOSFET Device is formulated, based on the Maxwellian approximation where the electron temperature is controlled by acoustic phonon scattering which simultaneously includes the hot electrons and the thermoelectric effects. The demonstration involving predicted current voltage characteristics and ring oscillator propagation delays reveals a significant benefit of velocity overshoot is also presented for circuit simulation. The extracted model describes current characteristics from linear to saturation operating regions with a single IV expression, and guarantees the continuities of Ids, conductance and their derivative throughout all Vgs, Vbs and Vds bias conditions. The model has been implemented in the circuit simulation such as HSPICE, Smart Spice and BSIM4v6. The new model has extensive built-in dependencies of important dimensional and processing parameters. Furthermore, the model accounts for all the major physical effects of the MOSFET characteristics.

In this paper a low complexity MIMO MC-CDMA receiver is proposed. We investigate the receiver performance and complexity in the case of despreading multicarrier code division multiple access signals (MC-CDMA) prior to V-BLAST detection in multiple input multiple output systems (MIMO). The proposed structure shows that for iterative detection, despreading before detection (DBD) reduces the effect of multiple access interference (MAI), and the reported results demonstrate improved bit error rate (BER) performance and user capacity of the system over despreading after detection (DAD). Furthermore, DBD results in reduced system complexity. The performance of both detectors is evaluated using computer simulations for a frequency selective slow Rayleigh fading channel.