atr2434 ATMEL Corporation, atr2434 Datasheet - Page 21

• Manufacturer Part Number: atr2434
• Description: Wirelessusb 2.4-ghz Dsss Radio Soc - Atmel Corporation
• Manufacturer: ATMEL Corporation

Table 21. Threshold Low
Table 22. Threshold High
4822C–ISM–09/04
Bit
7
6:0
Bit
7
6:0
Reserved
Reserved
Name
Reserved
Threshold Low
7
7
Name
Reserved
Threshold High
Addr: 0x1A
Addr: 0x19
6
6
Description
This bit is reserved and should be written with zero.
The Threshold Low value is used to determine the number of missed chips allowed when attempting to
correlate a single data bit of value 0. A perfect reception of a data bit of 0 with a 64 chips/bit PN code would
result in zero correlation matches, meaning the exact inverse of the PN code has been received. By setting
the Threshold Low value to 0x08 for example, up to eight chips can be erroneous while still identifying the
value of the received data bit. This value along with the Threshold High value determine the correlator count
values for logic 1 and logic 0. The threshold values used determine the sensitivity of the receiver to
interference and the dependability of the received data. By allowing a minimal number of erroneous chips the
dependability of the received data increases while the robustness to interference decreases. On the other
hand increasing the maximum number of missed chips means reduced data integrity but increased
robustness to interference and increased range.
Description
This bit is reserved and should be written with zero.
The Threshold High value is used to determine the number of matched chips allowed when attempting to
correlate a single data bit of value 1. A perfect reception of a data bit of 1 with a 64 chips/bit or a 32 chips/bit
PN code would result in 64 chips/bit or 32 chips/bit correlation matches, respectively, meaning every bit was
received perfectly. By setting the Threshold High value to 0x38 (64-8) for example, up to eight chips can be
erroneous while still identifying the value of the received data bit. This value along with the Threshold Low
value determine the correlator count values for logic 1 and logic 0. The threshold values used determine the
sensitivity of the receiver to interference and the dependability of the received data. By allowing a minimal
number of erroneous chips the dependability of the received data increases while the robustness to
interference decreases. On the other hand increasing the maximum number of missed chips means reduced
data integrity but increased robustness to interference and increased range.
5
5
REG_THRESHOLD_H
REG_THRESHOLD_L
4
4
Threshold High
Threshold Low
3
3
ATR2434 [Preliminary]
2
2
1
1
Default: 0x08
Default: 0x38
0
0
21