- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄382555 > STA400A (意法半導(dǎo)體) XMRADIO SDARS CHANNEL DECODER PDF資料下載
參數(shù)資料
| 型號： | STA400A |
| 廠商： | 意法半導(dǎo)體 |
| 英文描述： | XMRADIO SDARS CHANNEL DECODER |
| 中文描述： | XMRADIO衛(wèi)星數(shù)字收音機(jī)信道解碼器 |
| 文件頁數(shù)： | 14/117頁 |
| 文件大?。?/td> | 910K |
| 代理商： | STA400A |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁當(dāng)前第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁第99頁第100頁第101頁第102頁第103頁第104頁第105頁第106頁第107頁第108頁第109頁第110頁第111頁第112頁第113頁第114頁第115頁第116頁第117頁
STA400A
14/117
The second IF composite satellite signal, available at the IF2SA inputs, has the spectrum schematically shown
in Fig.7. The base band convertion of the selected satellite signal is done by programming the carrier NCO (act-
ing as local oscillator) of the demodulator. For demodulating the S1-Early Satellite signal the carrier NCO fre-
quency of the Early QPSK Demodulator must be equal to 6.095 + 0.92 = 7.015 MHz; for the S2-Late Satellite
signal the frequency at the carrier NCO output of the Late QPSK Demodulator must be 6.095 - 0.92 = 5.175
MHz.
The register map of the QPSK demodulators is described in section 2.2.
I/Q Mixer - Carrier NCO
The final downconvertion to baseband of the 2nd IF satellite signal is performed by a mixer and a local oscillator
implemented with an NCO and a Sin/Cos Look-up table (see figure 6). The signal coming from the IF Sampling
block is multiplied by the output of the quadrature NCO to produce the I and Q components of the baseband
signal. The NCO output are the sine and cosine functions obtained with a look-up table driven by a 28 bit phase
accumulator.
The IFFREQ register sets the frequency of the carrier NCO as given in the following:
F
c
= F
MCLK
x (IFFREQ)/2
28
,
where F
MCLK
is the clock frequency and IFFREQ is the 28 bit integer value loaded in the register.
For example, to program the S1-NCO to 7.015 MHz the IFFREQ register must be loaded with 04B13B14 (Hex)
equivalent to 78723860 (Dec).
The sine/cosine output frequency of the NCO is given by F
o
= (F
c
+ F
sw
+ PH
err
) x F
MCLK
/2
28
where Fc is the
nominal center frequency, F
sw
is the output of the frequency sweep generator, PHerr is the filtered phase error
from the carrier loop filter output and F
MCLK
/2
28
is the NCO frequency resolution.
The CARFREQ read only register gives the value of the actual carrier frequency after the lock condition has
been reached. This register can be used to measure the frequency offset between the local oscillator and the
incoming carrier.
The QCHS block of the I/Q mixer changes the sign of the Quadrature component in order to adapt the demod-
ulation process to a different rotation sense of the QPSK mapping.
Figure 7. Second IF Satellite Signal Spectrum
Fo
S1A
(S1B)
F (MHz)
S2A
(S2B)
Fo + 0.92
Fo - 0.92
Fo = 6.095 MHz
RRC Symbol freq = 1.64 MHz
roll-off factor = 15 %
S2 = Late Satellite
S1 = Early satellite
A = Ensemble A; B = Ensemble B
3.726
1.886
1.886
1.64
1.64
1.84
0.92
0.92
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| STA450A | XMRADIO SDARS SERVICE LAYER & SOURCE DECODER |
| STA508 | 40V 4.5A QUAD POWER HALF BRIDGE |
| STABP01 | GT 7C 7#16S SKT PLUG RTANG |
| STABP01D | GT 5C 5#16S SKT PLUG |
| STB10NA40 | N-Channel Enhancement Mode Fast Power MOS Transistor(N溝道增強(qiáng)模式快速功率MOSFET) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| STA400AV WAF | 制造商:Texas Instruments 功能描述: |
| STA400MTEP | 制造商:Rochester Electronics LLC 功能描述: 制造商:Texas Instruments 功能描述: |
| STA400MTEP/NOPB | 制造商:Texas Instruments 功能描述:Analog Multiplexer Dual 2:1 20-Pin TSSOP Rail |
| STA401 | 制造商:Distributed By MCM 功能描述:SUB ONLY SANKEN TRANSISOR ARRY 10-PIN SIP |
| STA401A | 制造商:Sanken Electric Co Ltd 功能描述:Trans Darlington NPN 70V 4A 10-Pin SIP Box 制造商:Sanken Electric Co Ltd 功能描述:TRANS ARRAY SINK DVR NPN 10-SIP 制造商:Panasonic Industrial Company 功能描述:TRANSISTOR SELL STA401A |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。