# Search results

1. ### Group delay related question

my prof ask me to calculate the phase of each wavelength from a relationship between group delay and wavelength: τ = A(λ-λo) τ: group delay λo = 1550nm λ: arbitrary wavelength in nm A: coefficient in ps/nm This formula shows us how to calculate the group delay, corresponds to a wavelength...
2. ### Which mathematical model is suitable for modelling a thin-film optical filter?

Recently, In DWDM systems, they use thin-film optical filter to construct OADM or OXC. I want to ask some expert here, in simulation, which mathematical model is suitable for modeling this type of filter used in optical network, and why?
3. ### Butterworth filter design problems? Need your help

I understand well the aspect mathematic of butterworth filter. My problem now is, how to calculate the coefficients of the denominator of the transfer function in s-domain of an analog butterworth filter without looking up in the table? Of course, we are given a fomula to calculate the poles...
4. ### Looking for info about optical filters

I want papers, books or articles on optical filters. If someone here has been working on this field, please share with me some documents and your experiences??? In addition, have you got some docs on Wavelength-Selective-Switch (WSS), please share here with us. I will not forget the HELP button ;)
5. ### Designing an active phased array in x-band

Re: active phased array Why don't you share them here in this board? Other members can benefit from it and give you their feedbacks!

7. ### PhD topic suggestion!!!

Well, from your point of view, The problem lies in the fact that, your university and also your infrastructure in your country do not support the manufacturing of a research product. So you should think about a thesis which ends only at simulation. And I think that, a project on antenna design...
8. ### What is the impact on communication when we use horizontal or vertical polarization?

Re: Polarization I think the problem here is how to match the polarization between transmitter and receiver in order to "gather" power from the transmitter at the recever-end. I have no idea about the differences between different polarizations of EM waves.
9. ### Software for antenna design simulation

Hi nazanin, if it's possible, could you please upload this software? Because I see that in my place, people prefer ADS the most so I want to familiarize with this software. Concerning about the l*i*c*e*n*c*e, could you send it via my email: haibinhle@hotmail.fr (It seems that this forum does...
10. ### Pcaad5: east antenna design software

antenna software -pcaad5 Is it usable for microstrip antenna design?
11. ### a book that will give mathematical details and the theory

But what do you want to design? You have to clarify your objectives so that the others can recommend you solutions If antenna design, you can start a search in this site. There's a plenty of books deal with this subjects, both on theory and implementation!!!
12. ### Software for antenna design simulation

I have a small project on microstrip antenna design and my prof recommend me ADS for simulation but it's too expensive to buy for a student. I asked him for a copy with my own PC but he refused and recommended me to work in his Lab. It takes time and I want to do this project in my home. Do you...
13. ### PhD topic suggestion!!!

@tieuquaybk: Before beginning your PhD work, I think you should attain the Master of Science degree first. And I think after 2 years of working on MSc thesis, you will get deeper into the RF domain. I would recommend you to think about your PhD dissertation in MIMO systems or in RF measurements
14. ### 8051 microcontroller starter book

8051 microconroller have you got the book "The 8051 Microcontrollers and Embedded Systems" by Mazidi? I have searched on this forum but there's only one thread with 4 chapters (from chapter 1 to 4). Have you got the others chapters, please share because I really need it now...
15. ### Questions on MSP430 about Program Counter, constant generator and bootstrap loader

I'm reading a book on MSP430 1. There's a phrase I do not understand: Why does Program Counter (PC) increment by 2 not by 1? 2. R2 and R3 act as a constant generators, what are the roles of constant generator? We can generate a constant by using an instruction like ADD or MOV? 3. What is...
16. ### What is it? Rogen's gradient projection

I'm a telecom engineer but I meet this definition in an article. Can some one explain to me the very basics about it or recommend me some lectures that deal with it??? Thank you in advance!
17. ### some beginner-level questions on uE?

1- Recently, What is the technology to produce a memory? I read an article about memory advancement but I do not understand it completely. It talks about NOR-gate and NAND-gate based technology but I dont know about this technology. Can some one here show me the answer as clear as possible...
18. ### Some very basic questions on antenne

thank you sinip, but one more question, what does it mean "balance" here, balance in what? and the coaxial is unbalanced in what?
19. ### Some very basic questions on antenne

- I know why we have to match the impedance of the generator and the one of the antenna. That is to done to get the most power of the generator at the antenne for radiate. Is this true? - I know about the Dipole but I dont know why if we do not have a coaxial connector, we have to use BALUN...
20. ### 8 bit temperature sensor

hih-3610 + adc0808 You want an electronic component which integrate all of three functions or discret components which assembled together to do these functions? If you are of the second case, I recommend you to use LM335 to gather temperature infors in the form of voltage, to put noise out of...