About 20 yrs ago I designed silicon for (non-military) GPS RX in mobiles (handsets). At the time I had to deeply study the system functions, timing, almanac, ephemerides, Gold codes, data frame structure, etc. This gave me DEEP respect for the original architects/designers who pulled this together and made it operational. But watching your video I have highest respect for YOUR ability to distill the key functional elements down into bite size explanations “understandable by mortals.” Very nicely done.
Thank you. Yes I must say I am thoroughly impressed by those engineers who designed all the various aspects of the system. We have an older gentleman working for the same company as me. He is well into his seventies. He has been designing much of the GPS technology that we develop for more than 4 decades. His knowldege is incomparable and we fear the day he finally retires. 🙂
Thank you so much for the explanation about the rough estimate of the satellite distance, which is needed to figure out how many full C/A code sequences we have and then add the calculated shift. I've assumed we need such an estimate and I was looking for this explanation, but I couldn't find it anywhere else. Thank you!
Thank you so much for the video, I am taking a drone course and had to learn how GPS works and was curious how time of signal passage is measured in one way ranging.
Watching this, a question popped into my mind: Does a C/A code have an upper limit of 1s in it. Is that number the same for all PRNs. If it is not, for a sequence of C/A code that all consists of 1s would be the most correlated? My possible answer: The distribution of 1s and 0s in the C/A code is designed to be pseudo-random, with an approximately equal number of 1s and 0s over the entire sequence.
Thank you, but I’m sorry, I don’t quite understand - where is the CA code that we’re bit shifting with respect to coming from? Anything sent from the SV to the receiver will be equally delayed, so what bit stream are we shifting and multiplying against? I’m sure it’s a simple answer 🙂
Each receiver has a copy of the bit code sting from each satellite. By comparing the bits (by shifting one of the strings) we can determine when the signal was sent and when it was received.
The clocks are not synchronized. The receiver clock error can be checked with the universal time available from the command center and the satellite clock error is calculated (to be shown in a later video).
@@MichelvanBiezen Is there already any video that you explained this synchronisation problem? In all your lectures there is only mention about "clock error" due to quartz clock drift in the receiver, but assuming that receiver clock is atomic clock, still remains the synchronisation problem for dermining pseudorange.
8 Two guns A and B can fire bullets at speed 1 km/s and 2 km/s respectively. From a point on a horizontal ground, they are fired in all possible directions. The ratio of maximum areas covered by the buyllets fired by the two guns, on the ground is: [Make video in question like this
About 20 yrs ago I designed silicon for (non-military) GPS RX in mobiles (handsets).
At the time I had to deeply study the system functions, timing, almanac, ephemerides, Gold codes, data frame structure, etc. This gave me DEEP respect for the original architects/designers who pulled this together and made it operational.
But watching your video I have highest respect for YOUR ability to distill the key functional elements down into bite size explanations “understandable by mortals.” Very nicely done.
Thank you. Yes I must say I am thoroughly impressed by those engineers who designed all the various aspects of the system. We have an older gentleman working for the same company as me. He is well into his seventies. He has been designing much of the GPS technology that we develop for more than 4 decades. His knowldege is incomparable and we fear the day he finally retires. 🙂
Sir, you are awesome, Respect you Sir
Thank you. Glad you liked it. 🙂
Thank you so much for the explanation about the rough estimate of the satellite distance, which is needed to figure out how many full C/A code sequences we have and then add the calculated shift. I've assumed we need such an estimate and I was looking for this explanation, but I couldn't find it anywhere else. Thank you!
Glad you liked it. It is indeed all about finding the accurate locations of the satellites and keeping VERY accurate time.
wow! This channel is gold! Thanks!
You're very welcome!
Thank you so much for the video, I am taking a drone course and had to learn how GPS works and was curious how time of signal passage is measured in one way ranging.
Glad it was helpful!
Wow . I am surprised. It’s just amazing
Thank you. Glad you liked it. 🙂
Watching this, a question popped into my mind:
Does a C/A code have an upper limit of 1s in it. Is that number the same for all PRNs. If it is not, for a sequence of C/A code that all consists of 1s would be the most correlated?
My possible answer: The distribution of 1s and 0s in the C/A code is designed to be pseudo-random, with an approximately equal number of 1s and 0s over the entire sequence.
Thank you, but I’m sorry, I don’t quite understand - where is the CA code that we’re bit shifting with respect to coming from?
Anything sent from the SV to the receiver will be equally delayed, so what bit stream are we shifting and multiplying against? I’m sure it’s a simple answer 🙂
Each receiver has a copy of the bit code sting from each satellite. By comparing the bits (by shifting one of the strings) we can determine when the signal was sent and when it was received.
@@MichelvanBiezen Does that assume that the sender and the receiver have synchronised clocks? The receiver knows what was sent at a specific time?
The clocks are not synchronized. The receiver clock error can be checked with the universal time available from the command center and the satellite clock error is calculated (to be shown in a later video).
Thank you, I think I get the picture 🙂
@@MichelvanBiezen Is there already any video that you explained this synchronisation problem? In all your lectures there is only mention about "clock error" due to quartz clock drift in the receiver, but assuming that receiver clock is atomic clock, still remains the synchronisation problem for dermining pseudorange.
Sir pls capasitor pe 1 video banao
We have a lot of videos on capacitors (in the physics section).
@@MichelvanBiezen ok sir
8 Two guns A and B can fire bullets at speed 1 km/s and
2 km/s respectively. From a point on a horizontal
ground, they are fired in all possible directions. The
ratio of maximum areas covered by the buyllets fired by
the two guns, on the ground is:
[Make video in question like this