| поискавой системы для электроныых деталей |
|
ADF7021 датащи(PDF) 29 Page - Analog Devices |
|
|
|||||||||||||||||||||||||||||
ADF7021 датащи(HTML) 29 Page - Analog Devices |
|
29 / 64 page ![]() Data Sheet ADF7021 Rev. B | Page 29 of 64 MODULATION AND FILTERING OPTIONS The various modulation and data filtering options are described in Table 11. Table 11. Modulation and Filtering Options Modulation Data Filtering R2_DB[4:6] BINARY FSK 2FSK None 000 MSK1 None 000 OQPSK with half sine baseband shaping2 None 000 GFSK Gaussian 001 GMSK3 Gaussian 001 RC2FSK Raised cosine 101 Oversampled 2FSK None 100 3-LEVEL FSK 3FSK None 010 RC3FSK Raised cosine 110 4-LEVEL FSK 4FSK None 011 RC4FSK Raised cosine 111 1 MSK is 2FSK modulation with a modulation index = 0.5. 2 Offset quadrature phase shift keying (OQPSK) with half sine baseband shaping is spectrally equivalent to MSK. 3 GMSK is GFSK with a modulation index = 0.5. TRANSMIT LATENCY Transmit latency is the delay time from the sampling of a bit/symbol by the TxRxCLK signal to when that bit/symbol appears at the RF output. The latency without any data filtering is 1 bit. The addition of data filtering adds a further latency as outlined in Table 12. It is important that the ADF7021 be left in transmit mode after the last data bit is sampled by the data clock to account for this latency. The ADF7021 should stay in transmit mode for a time equal to the number of latency bit periods for the applied modulation scheme. This ensures that all of the data sampled by the TxRxCLK signal appears at RF. The figures for latency in Table 12 assume that the positive TxRxCLK edge is used to sample data (default). If the TxRxCLK is inverted by setting R2_DB[28:29], an additional 0.5 bit latency can be added to all values in Table 12. Table 12. Bit/Symbol Latency in Transmit Mode for Various Modulation Schemes Modulation Latency 2FSK 1 bit GFSK 4 bits RC2FSK, Alpha = 0.5 5 bits RC2FSK, Alpha = 0.7 4 bits 3FSK 1 bit RC3FSK, Alpha = 0.5 5 bits RC3FSK, Alpha = 0.7 4 bits 4FSK 1 symbol RC4FSK, Alpha = 0.5 5 symbols RC4FSK, Alpha = 0.7 4 symbols TEST PATTERN GENERATOR The ADF7021 has a number of built-in test pattern generators that can be used to facilitate radio link setup or RF measurement. A full list of the supported patterns is shown in Table 13. The data rate for these test patterns is the programmed data rate set in Register 3. The PN9 sequence is suitable for test modulation when carrying out adjacent channel power (ACP) or occupied bandwidth measurements. Table 13. Transmit Test Pattern Generator Options Test Pattern R15_DB[8:10] Normal 000 Transmit Carrier 001 Transmit + fDEV tone 010 Transmit − fDEV tone 011 Transmit 1010 pattern 100 Transmit PN9 sequence 101 Transmit SWD pattern repeatedly 110 |
|
ссылки URL |
| Вашему бизинису помогли Аллдатащит? [ DONATE ] |
Что такое Аллдатащит | реклама | контакт | Конфиденциальность | Ссылка на техническое описание | обмен ссыками | поиск по производителю All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |