My MathCAD Files, all 2001 format.

System Design:



• The range expected from an FM system with and without Raleigh fading pdf

• Conversion dBm to Vemf & Vpp pdf

• VCO noise-floor & Q from Leeson model to get design values for a PLL pdf

• Two common PLL problems, phase-reference-spurs and VCO noise from the vtune resistor pdf

• FET PA harmonics and efficiency pdf

• Class-E PA design equations pdf

Filter Design and Microstrip Filters:



• Microstrip, stepped impedance low-pass filter. Type-1 pdf

• Microstrip, stepped impedance low-pass filter. Type-2 pdf

• Microstrip, coupled band-pass filter pdf

• Bandpass 3-stage coax cable filter pdf

• Bandpass 3-stage coax cable filter with tuning capacitors pdf

• Capacitatively coupled band-pass filter pdf

• Magnetically coupled band-pass filter pdf

• Simple gm-C filter pdf

• Microstrip, multi-section notch filter pdf

• Accurate Impedance (Zo) for microstrip lines, including a correction for line thickness pdf

• Accurate Zoo / Zoe for microstrip lines, including a correction for line thickness pdf

Directional Couplers and Splitters. These came from my thesis:



• Design of a discrete component RF directional coupler pdf

• Design of a discrete component branch-line RF directional coupler. Type-1 pdf

• Design of a discrete component branch-line RF directional coupler, Type-2 pdf

• Design of a transformer type of RF directional coupler pdf

• Dual frequency-band Wilkinson style RF power-divider pdf

• Very wideband quarter wavelength impedance transformer pdf

Assortment of IC Circuit and Component Design:



• Design a miller op-amp using simplified maths pdf

• Design of a band-gap voltage reference circuit pdf

• Design of planar inductors used on an IC pdf

• Summary of parallel plate capacitance equations pdf

My Thesis (2004):

I returned to university (Sept 2003 to July 2004) to study the second year of a Masters course in Radio Frequency Integrated Circuits (RFIC) at AAlborg University in Denmark.

Here is a link.

My project was to design, layout and test a lossless-feedback amplifier on a CMOS Integrated Circuit to work at 1.5 to 2GHz. The feedback improves the amplifier linearity without degrading the amplifier noise figure. This is the first time that such an amplifier has been built above 200MHz and also the first time that these transformer directional couplers were built on an IC. You can download my thesis (20 Meg) from here.

RF Splitter Design Software:

Discrete component splitter (80k). Easy to use GUI software to design passive component Wilkinson or Quad splitters. It generates an Aplac (.i) simulation file. Free to use. Screenshot.

RF Filter Design Software:

Filter Design (120k). Another easy to use GUI software to design passive LC filters and to create an Aplac (.i) simulation file. Free to use; Likely to be updated over the next few months. Screenshot.

Aplac Simulator:

A student version of Aplac was available. This was a very powerful spice type simulator with lots of RF circuit features including microstrip and coupled lines. It is a pity that it is no longer available but the spice netlist can be used in other simulators.

To run these on version 7.9 and above you need to select 'simulation' from the pull down menus as these files are written in the text format.