NXP Semiconductors freescale semiconductor MC13211, Справочное руководство

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MC1321x Introduction
MC1321x Reference Manual, Rev. 1.6
Freescale Semiconductor 1-11
Figure 1-4. Reported Power Level versus Input Power in Clear Channel Assessment Mode
Figure 1-5 shows energy detection/LQI reported level versus input power.
Figure 1-5. Reported Power Level Versus Input Power for Energy Detect or Link Quality Indicator
1.7.5 Modem Transmit Path Description
For the transmit path, the TX data that was previously written to the internal RAM is retrieved (Packet
Mode) or the TX data is clocked in via the SPI (Streaming Mode), formed into packets per the 802.15.4
PHY, spread, and then up-converted to the transmit frequency.
If the MC1321x is in Packet Mode, data is processed as an entire packet. The data is first loaded into the
TX buffer. The MCU then requests that the modem transmit the data. The MCU is notified via an interrupt
when the whole packet has successfully been transmitted.
In Streaming Mode, the data is fed to the MC1321x on a word-by-word basis with an interrupt serving as
a notification that the MC1321x is ready for more data. This continues until the whole packet is
-100
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-90 -80 -70 -60 -50
Input Pow er (dBm)
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802.15.4 Accuracy
and range Requirements
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Input Pow er Level (dBm)
R
e
po
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P
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L
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802.15.4 Accuracy
and Range Requirements