Subversion Repositories svnkaklik

Rev

Rev 1114 | Rev 1116 | Go to most recent revision | Show entire file | Ignore whitespace | Details | Blame | Last modification | View Log

Rev 1114 Rev 1115
Line 16... Line 16...
16
  * Support for any number of receivers in range 1 to 8
16
  * Support for any number of receivers in range 1 to 8
17
\enditems
17
\enditems
18
 
18
 
19
\sec Sampling frequency
19
\sec Sampling frequency
20
 
20
 
21
Sampling frequency is limited by the technical constrains in the trial design. This parameter is especially limited by the sampling frequencies of analog-to-digital conversion chips available on the market and interface bandwidth. Combination of the required parameters -- dynamic range requiring at least 16bit and a minimum sampling frequency of 1 MSPS leads to need of high end ADC chips which does not support such low sampling frequencies at all. Their minimum sampling frequency is 5 MSPS.
21
Sampling frequency is limited by the technical constrains in the trial design. This parameter is especially limited by the sampling frequencies of analog-to-digital conversion chips available on the market and interface bandwidth. Combination of the required parameters -- dynamic range requiring at least 16bit and a minimum sampling frequency of 1 MSPS leads to need of high end ADC chips which does not support such low sampling frequencies at all. Their minimum sampling frequency is 5$\ $MSPS.
22
 
22
 
23
We calculate minimum data bandwidth data rate for eight receivers, 2 bytes per sample and 5MSPS as $8 * 2 * 5e6 = 80$ MB/s. Such data rate is at the limit of real writing speed o classical HDD and it is almost double of real bandwidth of USB 2.0 interface. 
23
We calculate minimum data bandwidth data rate for eight receivers, 2 bytes per sample and 5MSPS as $8 \cdot 2 \cdot 5\cdot 10^6 = 80\ $MB/s. Such data rate is at the limit of real writing speed o classical HDD and it is almost double of real bandwidth of USB 2.0 interface. 
24
 
24
 
25
 
25
 
26
\sec System scalability
26
\sec System scalability
27
 
27
 
28
For analogue channels scalability, special parameters of ADC modules are required. Ideally, there should be a separate output for each analogue channel in ADC module. ADC module must also have separate outputs for frames and data output clocks. These parameters allow for conduction at relatively low digital data rates. As a result, the digital signal can be conducted even through long wires. 
28
For analogue channels scalability, special parameters of ADC modules are required. Ideally, there should be a separate output for each analogue channel in ADC module. ADC module must also have separate outputs for frames and data output clocks. These parameters allow for conduction at relatively low digital data rates. As a result, the digital signal can be conducted even through long wires.