Figure of Merit (FoM) of LNA and Mixer

There are many different definitions of FoM for different LNAs (wideband LNA, low power LNA, etc.).

For low power LNA, one definition is [1]

Wherein, the Gain is power gain.

Another two definitions are [2]:

A Mixer's FoM can be defined as [3]:

References:

[1] LEE, H., MOHAMMADI, S. A 3GHz subthreshold CMOS low noise amplifier. In Radio Frequency Integrated Circuits (RFIC)

Symposium, 2006, p. 4.
[2] Linten, D.; Aspemyr, L.; Jeamsaksiri, W.; Ramos, J.; Mercha, A.; Jenei, S.; Thijs, S.; Garcia, R.; Jacobsson, H.; Wambacq, P.; Donnay, S.; Decoutere, S.;
VLSI Circuits, 2004. Digest of Technical Papers. 2004 Symposium on, 17-19 June 2004 Page(s):372 - 375
 
http://wwwtw.vub.ac.be/elec/Papers%20on%20web/Papers/DLinten/LintenVLSI2004.pdf

[3] Vidojkovic, V. Van der Tang, J. Leeuwenburgh, A. Van Roermund, A.  Circuits and Systems, 2003. ISCAS '03. Proceedings of the 2003 International Symposium on,  25-28 May 2003, Volume: 2, On page(s): II-300- II-303 vol.2

The basic of ZigBee Testing

Transmitter Testing: http://www.rfdesignline.com/howto/204203433

Receiver Testing: http://www.rfdesignline.com/howto/204203440;jsessionid=YZDS2AQY40CADQE1GHRSKH4ATMY32JVN?pgno=1

Post Layout Simulation with Cadence Netlist/Model in ADS2008

ADS2005,06,08 are able to read cadence Model/netlist, good feature!

The link below tells how to do post layout simulation with calibre extracted model/netlist.

http://www.agilentads.com/5_RFIC/ADS2006_2008_Post_Sim_w_Spectre_Model.pdf

or https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BwHwG2zPevKbMzMwMzU1OWUtNzRhOC00Y2Y1LTk4YTgtY2ZjMDA3MDU5ZmI1&hl=en&authkey=CJHioJ8E
Reminder: For any core circuit, the generated netlist must be defined as subcircuit. ADS does not recognize the netlist if it is not defined as subcircuit. The pin information are only available when defining subcircuit.

Input periodic sources can't be used in autonomous circuits

If your oscillator circuit does not contain a stimulus to start the oscillator, you must run


a transient analysis before you run this PSS analysis. From the transient analysis you save the node voltages and use them as initial conditions to start the oscillator in the PSS analysis.

With older cadence version, an impulse current can be used to stimulate the oscillator, but must be careful with new cadence version, it shows an error "periodic input signal, which is inconsistent with autonomous circuits". A quick solution is to leave the period of the impulse current source to be empty, or use a VPWL/IPWL to start the oscillations.

MSK identical to OQPSK with half-sine pulse shaping

OQPSK with half-sine pulse shaping is identical to MSK.

FSK modulation and demodulation can be used for OQPSK.

Detailed analysis is given in the below link:

http://www.dsplog.com/2009/06/16/msk-transmitter-receiver/

How to convert amplifier's input referred voltage noise to noise figure

In RF system design, noise figure is parameter to calculate receiver's sensitivity. But analog base-band specify noise with input or output referred voltage noise. How to convert it to noise figure? See the article "Calculating noise figure in op amps" below:

http://focus.ti.com/lit/an/slyt094/slyt094.pdf
Another article tells "Matching the noise performance of the operational amplifier to the ADC"
http://focus.ti.com/lit/an/slyt237/slyt237.pdf

Three methods of measureing noise figure of LNA/Mixer

From the below link:
http://pdfserv.maxim-ic.com/en/an/AN2875.pdf


Summary


In this article, three methods to measure the noise figure of RF devices are discussed. They each have

advantages and disadvantages and each is suitable for certain applications. Below is a summary table of the pros

and cons. Theoretically, the measurement results of the same RF device should be identical, but due to

limitations of RF equipment (availability, accuracy, frequency range, noise floor, etc), we have to carefully

choose the best method to get the correct results.