Author Archives: Marcus

the Doppler effect (classical)

The Doppler effect is noth­ing real­ly new. It’s well-known that Doppler fre­quen­cy shift occurs for sound as well as light; there are, how­ev­er, some sub­tle dif­fer­ences between the two, owing main­ly to Einstein’s spe­cial the­o­ry of rel­a­tiv­i­ty. This arti­cle describes the clas­si­cal Doppler effect as it occurs e.g. for sound waves and in which the […]

TiddlyWiki – incoming Links

There are sit­u­a­tions when you need to have a list of all the tid­dlers that link to some oth­er tid­dlers in your Tid­dly­Wi­ki, e.g. when renam­ing that oth­er tid­dler and hav­ing to update all the ref­er­ences to it. Some plu­g­ins out there give such lists,…

Basics of Doppler Vibrometry

This post has been over­due for quite a while now. I orig­i­nal­ly intend­ed to post some­thing about what I do at work soon after I start­ed my new job. That was more than a year ago; time real­ly does fly. Some­how there was always some­thing else already in the pipeline and I nev­er got around […]

O’ahu, Hawai’i

Final stop: O’ahu. Waiki­ki is just a tourist trap, but for­tu­nate­ly O’ahu has more to offer than crowd­ed beach­es, shops and Asian food. Here’s proof:

Maui, Hawai’i

After a week on the Big Island, we head­ed over to Maui. Here are some panoram­ic high­lights…  

my favorite focal lengths

I have been mean­ing to some­thing like this for quite a while, plot­ting the dis­tri­b­u­tion of the focal lengths used in the pic­tures I shoot, to see which por­tions of the zoom range get the most action. Here is the graph for our recent vaca­tion on Hawai’i, obtained using the Light­room 4 beta and Jef­frey […]

Signal Statistics for Nyquist WDM / OTDM

A while back I post­ed an arti­cle on Sig­nal Sta­tis­tics for OFDM. Orig­i­nal­ly, this would have includ­ed OTDM also, but it grew too long. So it was split into two parts. This is the sec­ond part. Please read the orig­i­nal arti­cle first, as it explains much of the ter­mi­nol­o­gy and the present arti­cle by itself […]

Big Island, Hawai’i

I am still catch­ing up to get­ting some order into the pic­tures I took dur­ing our last vaca­tion on Hawai’i. And that was back in Sep­tem­ber! Any­way, here are some of the bet­ter panora­mas from our first stop, Big Island. Click through for the large ver­sion at flickr, with a short descrip­tion.

Signal Statistics for OFDM

Here is some­thing that recent­ly piqued my inter­est (and kept me busy for the bet­ter part of last week). It could be (mar­gin­al­ly) inter­est­ing for peo­ple which work on OFDM or Nyquist WDM and – as far as I know – no one has looked at this in more detail…

Series Expansions

Some­thing I made back in July. Since then it shows up at the bot­tom of these here pages in the menu rib­bon, but I nev­er wrote a prop­er post about it. I guess it deserves a lit­tle more pub­lic­i­ty since I do use it quite reg­u­lar­ly. So here is my orig­i­nal descrip­tion for the cheat […]