AT86RF212 Atmel Corporation, AT86RF212 Datasheet - Page 85

• Manufacturer Part Number: AT86RF212
• Manufacturer: Atmel Corporation

Specifications of AT86RF212

• Max. Operating Frequency: 0 MHz
• Crypto Engine: AES
• Operating Voltage (vcc): 1.8 to 3.6
• Frequency Band: 700/800/900MHz
• Max Data Rate (mb/s): 1
• Antenna Diversity: No
• External Pa Control: Yes
• Power Output (dbm): 10
• Receiver Sensitivity (dbm): -110
• Receive Current Consumption (ma): 9.0
• Transmit Current Consumption (ma): 18 at 5dBm
• Link Budget (dbm): 120

6.6.3 Data Interpretation
6.6.4 Interrupt Handling
6.6.5 Measurement Time
8168C-MCU Wireless-02/10
The sub-register CCA_ED_THRES of register 0x09 (CCA_THRES) defines the receive
power threshold of the “energy above threshold” algorithm. The threshold is calculated
by
Any received power above this level is interpreted as a busy channel.
Note that it is not recommended to manually initiate a CCA request when using the
Extended Operating Mode.
The current channel status (CCA_STATUS) and the CCA completion status
(CCA_DONE) are accessible through register 0x01 (TRX_STATUS). Note that register
bits CCA_DONE and CCA_STATUS are cleared in response to a CCA_REQUEST.
The completion of a measurement cycle is indicated by CCA_DONE = 1. If the radio
transceiver detects no signal (idle channel) during the CCA evaluation period, the
CCA_STATUS bit is set to 1; otherwise, it is set to 0.
When using the “energy above threshold” algorithm, a received power above V_THRES
level is interpreted as a busy channel.
When using the “carrier sense” algorithm (i.e. CCA_MODE = 0, 2, and 3), the
AT86RF212 reports a busy channel upon detection of a PHY mode specific
IEEE 802.15.4 signal above RSSI_BASE_VAL [dBm] (see Table 6-25). The
AT86RF212 is also capable of detecting signals below this value, but the detection
probability decreases with decreasing signal power. It is almost zero at the radio
transceivers sensitivity level (see parameter 10.7.1 on page 154).
Interrupt IRQ_4 (CCA_ED_DONE) is issued at the end of a manually initiated CCA
measurement.
Note
• A CCA request should only be initiated in Basic Operating Mode RX states.
The response time of a manually initiated CCA measurement depends on the receiver
state.
In RX_ON state, the CCA measurement is done over 8 symbol periods and the result is
accessible upon the event IRQ_4 (CCA_ED_DONE) or upon CCA_DONE = 1 (register
0x01, TRX_STATUS).
In BUSY_RX state, the CCA measurement duration depends on the CCA mode and the
CCA request relative to the detection of the SHR. The end of the CCA measurement is
indicated by IRQ_4 (CCA_ED_DONE). The variation of a CCA measurement period in
BUSY_RX state is described in Table 6-29.
Otherwise, the radio transceiver generates IRQ_4 (CCA_ED_DONE) and sets the
register bit CCA_DONE = 1, without actually performing a CCA measurement.
V_THRES [dBm] = RSSI_BASE_VAL + 2.07 ⋅ CCA_ED_THRES .
AT86RF212
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