STS1TX datasheet(40/70 Pages) STMICROELECTRONICS

40 / 70 page

Transmission and reception

STS1TX

40/70

DocID025109 Rev 1

OOK and ASK

If MOD_TYPE = 2 and power ramping is enabled, then ASK is used; otherwise, if

MOD_TYPE = 2 and power ramping is disabled, then OOK is used.

When OOK is selected, a bit '1' is transmitted with the power specified by

PA_POWER[PA_LEVEL_MAX_INDEX], a bit '0' is transmitted with the power specified by

PA_POWER[0](normally set to PA off).

When ASK is selected, a bit '1' is transmitted with a power ramp increasing from

PA_POWER[0] to PA_POWER[PA_LEVEL_MAX_INDEX], a bit '0' is transmitted with a

power ramp decreasing from PA_POWER[PA_LEVEL_MAX_INDEX] to PA_POWER[0].

The duration of each power step is 1/8 of the symbol time.

If more '1's are transmitted consecutively, the PA power remains at

PA_POWER[PA_LEVEL_MAX_INDEX] for all '1's following the first one; If more '0's are

transmitted consecutively, the PA power remains at PA_POWER[0] for all '0's following the

first one.

CW mode

For test and measurement purposes the device can be programmed to generate a

continuous wave carrier without any modulation by setting the CW field of the MOD0

transmitter in TX state for an undefined period of time.

9.3.1

Data rate

The data rate is controlled by the MOD0 and MOD1 registers according to the following

formula:

Equation 8

where:

•

DATARATE_M is an 8-bit integer ranging from 0 to 255

•

DATARATE_E is a 4-bit integer ranging from 0 to 15

•

fclk is the digital clock frequency (typically 26 MHz).

The minimum data rate at fclk = 26 MHz is about 25 Hz; the maximum data rate is about 1.6

MHz. Be advised that performance for such values is not guaranteed.

9.4

Data coding and integrity check process

9.4.1

FEC

The device provides hardware support for error correction and detection.

Error correction can be either enabled or disabled according to link reliability and power

consumption needs. Convolutional coding with a rate=½ and k=4 is applied on the payload

and CRC before transmission (poly [13,17]).

DataRate

fclk

256 DATA_RATE_M

() 2

DATARATE_E

⋅

-------------------------------------------------------------------------------------------------------

⋅

STS1TX Datasheet(PDF) 40 Page - STMicroelectronics

STS1TX Datasheet(HTML) 40 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70

Datasheet Descarga

Enlace URL