pazar
Üye
- Katılım
- 27 Ocak 2013
- Mesajlar
- 3
- Puanları
- 1
merhaba arkadaşlar, ben erasmus ile bulunduğum ülkede bir proje ödevi aldım, daha doğrusu bu projeye maruz bırakıldım.
proje şu:
Hallo,The file attached (15.txt) contains an example signal that could be recorded (maybe by the intelligence ) during dialling a phone number, but contains also some distortions (noise, etc). The dialling of number was done using dual-tone multi-frequency signaling (DTMF). You tasks are as follows:1) Plot the signal in time domain, and determine duration of the tones as well as pauses ( in seconds or miliseconds).2) Plot of Fourier amplitude spectrum of the whole signal. Pay attention that horizontal axis should be in Hz (thus sampling rate was given below)3) Plot short-time Fourier transform aiming to reveal the dialled numer and try to characterize kind of distortions. Determine time-window length using results obtained in 1).4) You may find to whom is the recorded phone number.In order to achieve the mentioned above goals sample rate is required - 48000 samples/second. yüklediğim dosyada binlerce sayı var. 1. soruyu yaptım ama sonraki soruları yapamadım. hele ki telefon numarasının nasıl bulunacağı hakkında en ufak bir fikrim bile yok. yardımcı olabilecek arkadaşlar varsa, çok makbule geçer. şimdiden teşekkürler.
proje şu:
Hallo,The file attached (15.txt) contains an example signal that could be recorded (maybe by the intelligence ) during dialling a phone number, but contains also some distortions (noise, etc). The dialling of number was done using dual-tone multi-frequency signaling (DTMF). You tasks are as follows:1) Plot the signal in time domain, and determine duration of the tones as well as pauses ( in seconds or miliseconds).2) Plot of Fourier amplitude spectrum of the whole signal. Pay attention that horizontal axis should be in Hz (thus sampling rate was given below)3) Plot short-time Fourier transform aiming to reveal the dialled numer and try to characterize kind of distortions. Determine time-window length using results obtained in 1).4) You may find to whom is the recorded phone number.In order to achieve the mentioned above goals sample rate is required - 48000 samples/second. yüklediğim dosyada binlerce sayı var. 1. soruyu yaptım ama sonraki soruları yapamadım. hele ki telefon numarasının nasıl bulunacağı hakkında en ufak bir fikrim bile yok. yardımcı olabilecek arkadaşlar varsa, çok makbule geçer. şimdiden teşekkürler.
