JN5148/001,531 NXP Semiconductors, JN5148/001,531 Datasheet - Page 29

• Manufacturer Part Number: JN5148/001,531
• Description: Microcontrollers (MCU) 32bit RISC 2.4GHz
• Manufacturer: NXP Semiconductors

Specifications of JN5148/001,531

• Core: RISC
• Operating Supply Voltage: 2 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-56
• Minimum Operating Temperature: - 40 C
• Lead Free Status / Rohs Status: Details

8.2 Modem
The modem performs all the necessary modulation and spreading functions required for digital transmission and
reception of data at 250kbps in the 2450MHz radio frequency band in compliance with the IEEE802.15.4 standard. It
also provides a high data rate modes at 500 and 667kbps.
Features provided to support network channel selection algorithms include Energy Detection (ED), Link Quality
Indication (LQI) and fully programmable Clear Channel Assessment (CCA).
The Modem provides a digital Receive Signal Strength Indication (RSSI) that facilitates the implementation of the
IEEE 802.15.4 ED function and LQI function.
The ED and LQI are both related to receiver power in the same way, as shown in Fig19. LQI is associated with a
received packet, whereas ED is an indication of signal power on air at a particular moment.
The CCA capability of the Modem supports all modes of operation defined in the IEEE 802.15.4 standard, namely
Energy above ED threshold, Carrier Sense and Carrier Sense and/or energy above ED threshold.
© NXP Laboratories UK 2010
Sigma-Delta
Modulator
IF Signal
VCO
Gain
Figure 19 Energy Detect Value vs Receive Power Level
AGC
Modulation
Figure 18 Modem Architecture
JN-DS-JN5148-001 1v6
Demodulation
RX
TX
Spreading
(Despreading)
Detection
Symbol
Interface
RX Data
Interface
TX Data
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