Indlela Yokwenza Umsakazo Wedijithali Nge-DSP
Umsakazo wedijithali usuthandwa kakhulu ngenxa yekhono lawo lokuletha ikhwalithi yomsindo engcono, ukusetshenziswa kahle kwe-frequency spectrum, kanye nezici ezengeziwe ezifana ne-metadata yolwazi lwengoma. Enye yezingxenye ezibalulekile ekuthuthukisweni komsakazo wedijithali ukusetshenziswa kwe-Digital Signal Processor (DSP). Lesi sihloko sizoxoxa ngezinyathelo ezihilelekile ekuthuthukiseni umsakazo wedijithali kusetshenziswa i-DSP.
I-Pendahuluan
I-DSP, noma i-Digital Signal Processor, iyi-microprocessor eyenzelwe ngqo ukucutshungulwa kwesignali yedijithali ngesikhathi sangempela. Ngokomongo womsakazo wedijithali, i-DSP iguqula izimpawu ze-analog zibe zedijithali, icubungula lezo zimpawu, bese ekugcineni iguqula izimpawu zedijithali zibe izimpawu ze-analog ezizwakalayo.
Ukuze kwenziwe umsakazo wedijithali, kudingeka izingxenye eziningana eziyinhloko, okungukuthi:
1. I-Antenna: Ukwamukela amasignali omsakazo.
2. I-Tuner: Ukukhetha imvamisa yomsakazo oyifunayo.
3. I-DSP: Yokucubungula isignali yedijithali.
4. I-DAC (I-Digital-to-Analog Converter): Ukuguqula amasignali edijithali abe amasignali e-analog.
5. Isipikha esikhulu noma i-earphone: Yokukhipha umsindo.
Isinyathelo Sokuqala: Ukukhetha Izingxenye
1. I-Antena
I-antenna esetshenziswayo kumele ivumelane nemvamisa ofisa ukuyithola. Kumsakazo we-FM, i-antenna ye-telescopic noma i-antenna elula ye-monopole ivame ukusetshenziswa.
2. I-Tuner
I-tuner ingaba yimojuli elungele ukusetshenziswa noma ingxenye efana ne-chip ye-Si4703 noma ye-TEA5767. Lawa mamojuli ngokuvamile eza ne-I2C noma i-SPI interfacing, okwenza kube lula ukulawula imvamisa usebenzisa i-microcontroller.
3. I-DSP
Ukukhethwa kwe-DSP yingxenye ebaluleke kakhulu. Amanye ama-DSP avamile asetshenziswa ezinhlelweni zomsakazo afaka:
– Uchungechunge lwe-Texas Instruments (TI) TMS320
– Uchungechunge lwe-SHARC lwamadivayisi e-Analog (ADI)
– Uchungechunge lwe-STM32 olunezingxenye ze-DSP
4. I-DAC
I-DAC efana ne-PCM5102 noma i-ES9018, okuyi-DAC enekhwalithi enhle yomsindo, ingasetshenziswa ukuguqula isignali yedijithali ibuyele esignalini ye-analog.
5. Isipikha esikhulu
Ungasebenzisa izipikha ezisebenzayo noma usebenzise imodyuli encane ye-amplifier njenge-PAM8403 ukuze ukhiqize umsindo ocacile nophakeme.
Umklamo Wedivayisi
Uhlelo Lwebhulokhi
1. I-Antena -> 2. I-Tuner -> 3. I-DSP -> 4. I-DAC -> 5. Isipikha
Ukucubungula okuyinhloko kwalolu hlelo kuse-DSP, lapho isignali itholwa yi-antenna bese ikhethwa yi-tuner, bese ingena ku-DSP ukuze icutshungulwe ngedijithali, bese ekugcineni iguqulwa ibe isignali ye-analog yi-DAC bese iphuma nge-loudspeaker.
Isimiso Sesekethe
1. I-Antena
- Umdwebo olula we-antenna exhunywe kokufakwayo kwe-tuner.
2. Imojuli Yokushuna
– Umdwebo wokuxhumana phakathi kwe-tuner kanye ne-microcontroller esetshenziselwa ukulawula imvamisa.
3. I-DSP
– Umdwebo wokuxhuma we-DSP oxhunywe ku-tuner ukuze uthole amasignali okufaka futhi oxhunywe ku-microcontroller ukuze kulayishwe uhlelo.
4. I-DAC
– Umdwebo wokuguqulwa kwesignali yedijithali kusuka ku-DSP kuya kusignali ye-analog exhunywe kwisandisi-zwi.
5. Isipikha esikhulu
– Umdwebo olula wokuxhuma isikhulumi ne-amplifier uma kudingeka.
Ukusetshenziswa kwe-Firmware
Uma ihadiwe isiqediwe, isinyathelo esilandelayo ukuthuthukisa i-firmware ezosebenza ku-microcontroller kanye ne-DSP.
Ukulawula i-Tuner
Okokuqala, qiniseka ukuthi i-microcontroller yakho iyakwazi ukuxhumana ne-tuner. Kumamojula asebenzisa ukuxhumana kwe-I2C noma kwe-SPI, kuzodingeka uhlanganise umtapo wezincwadi we-I2C/SPI ku-microcontroller yakho.
Ikhodi yesibonelo yokulawula imojuli ye-TEA5767 tuner nge-Arduino:
"`cpp
Faka
ukusetha okungenalutho () {
I-Wire.begin(); // Ukuqaliswa kwe-I2C
Serial.begin (9600);
setFrequency(101.1); // Setha imvamisa ibe yi-101.1MHz
}
i-loop engekho () {
// akudingeki
}
i-void setFrequency (imvamisa yokuntanta) {
imvamisa ye-uint16_tB = 4 (imvamisa 1000000 + 225000) / 32768;
i-buffer yebhayithi [5];
i-buffer[0] = imvamisaB >> 8;
i-buffer[1] = imvamisaB kanye ne-0XFF;
i-buffer[2] = 0xB0;
i-buffer[3] = 0x10;
i-buffer[4] = 0x00;
I-Wire.startTransmission (0x60);
I-Wire.write(i-buffer, 5);
I-Wire.endTransmission();
}
``
Ukucubungula Isignali nge-DSP
Ukuhlela i-DSP kungaba yinkimbinkimbi kakhulu kuye ngohlobo kanye namakhono e-DSP. Isibonelo, nge-Texas Instruments DSP, cishe uzosebenzisa i-Code Composer Studio (CCS) ukuthuthukisa nokulayisha ikhodi ku-DSP.
Isibonelo sekhodi ye-pseudo ye-DSP ekhipha isignali ye-FM:
"`cpp
i-void main() {
initDSP(); // Qalisa i-DSP
ngenkathi (1) {
// Funda isignali evela ku-tuner
isignaliAnalog = fundaI-AnalogInput();
// Ukucutshungulwa kwesignali yedijithali
isignaliDigital = i-analogToDigital (isignaliAnalog);
i-demodulatedSignal = FM_Demodulate(signalDigital);
// Guqula ubuyele esignalini ye-analog
outputSignal = digitalToAnalog(demodulatedSignal);
// Thumela ku-DAC
sendToDAC(outputSignal);
}
}
``
Ukusetha i-DAC
Ngemva kokuthi ukucubungula sekuqediwe ku-DSP, isignali yedijithali idinga ukuguqulwa ibuyiselwe ku-analog kusetshenziswa i-DAC. Lokhu kusetha kuvame ukwenziwa nge-I2C noma i-SPI. Qinisekisa ukuthi i-DAC oyisebenzisayo iyahambisana nokukhishwa kwesignali yedijithali evela ku-DSP.
Isibonelo sekhodi esilula sokulawula i-PCM5102 DAC nge-Raspberry Pi:
"`python
ngenisa i-smbus
ibhasi = smbus.SMBus(1)
ikheli = 0x4C
i-def set_volume(ivolumu):
i-bus.write_byte_data(ikheli, 0x00, ivolumu)
Setha ivolumu ezingeni elithile isibonelo 0x7F
ivolumu_yokusetha(127)
``
Ukuhlola Nokulungisa Amaphutha
Uma yonke isekethe isixhunyiwe futhi i-firmware isilayishiwe, isinyathelo esilandelayo ukuhlola ukuqinisekisa ukuthi zonke izingxenye zisebenza kahle.
Amathiphu Okuhlola
1. Yenza Ukuhlolwa Okungeziwe: Hlola ingxenye ngayinye ngokwehlukana ngaphambi kokuyihlanganisa.
2. Sebenzisa i-Oscilloscope: Ukubuka isimo segagasi lesiginali ezindaweni ezahlukene kusekethe.
3. Ukulungisa Amaphutha Okwengeziwe: Uma kunenkinga, hlukanisa inkinga nengxenye ye-HF ngaphambi kokungena ku-DSP.
4. Naka ukuphazamiseka: Indawo ye-antenna kanye nokuvikela kungathinta ikhwalithi yesignali.
Okokugcina, uma zonke izingxenye zisebenza kahle, ungalalela umsakazo wedijithali onekhwalithi yomsindo ecacile ohlelweni olulakhile.
Isiphetho
Ukwakha umsakazo wedijithali nge-DSP kudinga ukuqonda okuqinile kwehadiwe yesiginali yedijithali kanye nokuhlela. Ngokuhlela ngokucophelela kanye nokukhetha izingxenye ezifanele, ungakha umsakazo wedijithali wekhwalithi ephezulu. I-DSP inikeza ukuguquguquka ekucubungulweni kwesiginali futhi ivumela izici ezengeziwe ezingenakwenzeka ngezindlela zendabuko ze-analog. Zijabulise ngokwakha umsakazo wakho wedijithali futhi ujabulele izithelo zomsebenzi wakho!
