Class-F Power Amplifiers for WCDMA Base Station Transmitters

Vana Venkataramani

CWTVirginia Tech

January 16 2004

This presentation focuses on the models, components, and performance of Choir

AlgorithmAlgorithmModels and Algorithms

Real-Time Switched Ethernet

RM

GUIGUI

User input

Host 1 Host n

Meta-sched

POSIX OS

thread code

RTSL

Meta-sched

POSIX OS

thread code

RTSL

Components of Choir

Performance of Choir

2

This presentation will discuss how to use counter 0 and counter 2 for project 1

Use counter 0 for the 1 second delay

CE 45 34 00CE 45 34 01CE 45 34 02...

ABCDE...ZYXWV...

Use counter 2 for the0.5 second delay

This delay method can result in an error of up to 1 period length

Use a small period with more iterations for less error

Loop entered Loop exited

Error for sample code is 1 ms

Example for i = 1:

ABCDE... ZYXWV...

The startup.asm file contains your segment definitions and handles initializations

If _main() should ever return, we just go back and start the program over.

public startstart PROC NEAR

; set up DSmov ax, DGROUPmov ds, ax

; set up SS and SPmov ss, axlea sp, TOPS

; run user programcall _main

; if the user program returns, then reset

jmp startstart ENDP

The designed amplifier shows very good performance throughout the WCDMA band

High efficiency (60%) has been achieved

Class-AB linearity is maintained (IMD = -30 dBc)

Good harmonic suppression is achieved (-60 dBc)

6

The graphics user interface helps in composing systems and visualizing algorithm outputs

Composing system

Visualizing algorithm outputs

7

In summary, multi-criteria scheduling insoft real-time systems shows much promise

Soft time constraints provide more flexibility in scheduling

Multiple criteria need to be considered in real world

Important applications are envisioned

Questions?8