Recent content by sajib333

Hello Thanks. I have two question from your answer. ''If you send an electrical signal of 10 kHz into a copper wire antenna then to have its electromagnetic wave wirelessly reach a distant point you must use a very long antenna.'' 1) What did you mean by '' wirelessly reach a distant...

Thanks! I already read your link, and I believe it is what it should be. However,please consider the following text again. '" AM radio stations transmit audio signals, with a range from 20 Hz to 20 kHz, using carrier waves with a range from 500 kHz to 1.7 MHz. If they were to transmit audio...

Thanks! I understand the point. All the low frequency waves need to be superimposed on to a carrier wave, so that the message can be transmitted. But, my question is on the second line of the following paragraph, where they mentioned if a carrier were not used , then the antenna height would...

The following text is not only defined in an weblink (i.e http://www.ni.com/white-paper/3002/en ) , but also written in a number of other sites (with the same menaing). ''" AM radio stations transmit audio signals, with a range from 20 Hz to 20 kHz, using carrier waves with a range from 500...

Hello Everyone! About Amplitude Modulation, Usually it is seen in the book or web that (e.g. http://www.ni.com/white-paper/3002/en ) '''' The message signal can be represented by m(t) = Mb cos(2πfb + φ) and the carrier signal can be represented by c(t) = Ac cos(2πfc + φ), Now...

Hej! Isnt it the maximum frequency of a signal actually means(or equal to) the highest/largest harmonics of that signal?

Yah, This is what I know actually. But this is not what you have been asked to answer, please read my question before you reply, I appreciate your time. thanks.

Re: Confused! As far as I understand, the 4 Hz in an audio signal would refer to its "mean" frequency, so to speak. It is practically impossible to to produce a signal (of any kind, if I´m not wrong) with a perfectly constant frequency. So the 4 Hz would be the frequency that you perceive...

Thanks! Thanks a lot, well, we know frequency= Light speed/ Wavelength, f= C/Lemda. Accordingly I found its written in one website " If we like to transmit a low frequency signal directly, for instance an 1 KHz audio signal, from the equation F= C/ Lemda, we get the corresponding wavelength...

If it is the case then the users are suppose to use total 25 MHz bandwidth allocated for the CDMA system (either uplink /downlink). However, it is known that the user use 1.25 MHz band. Why it is it?

Hello for CDMA (800 or 850 whatever you call), the total frequency range is: 824–849 MHz/869–894 MHz (uplink/downlink) Consider either up-link or down-link, the total band is 25 MHz. We know CDMA use 1.25 MHz band, hence the number of total channel/band for either link should be...

hello From wiki.. ''There are a fixed number of orthogonal codes, timeslots or frequency bands that can be allocated for CDM (Sync CDMA), TDMA, and FDMA systems, which remain underutilized (to fail to utilize fully) due to the bursty nature of telephony and packetized data transmissions...

For Amplitude Modulation, it is understood that the bandwidth of a passband signal is always twice as much as that of a baseband signal, for example if the bandwidth/max frequency of a message/baseband signal is 1 kHz and a carrier of 1 MHz is modulated with this baseband, then a "sum"...

A single wave source, just like a audio signal, for instance.

Confused! -- Max frequency versus fundamental frequency Hello I understand the following question is very silly, however I am not sure about the answer. Let's consider we are saying there is a signal with a frequency of 4 Hz (for example). In such a statement, does it mean the maximum...