The Zigbee/IEEE 802.15.4 standard is described alongwith the design
methodology used to develop a single-device solution. Zigbee wireless technology is used to address the low cost, low power radio solu tions for fairly simple wireless applications within our homes, office and the industrial environment. reliability, interoperability, security and low power consumption are the important features of the system. The low-cost and low-power targets must be met while designing the IEEE 802.15.4/Zigbee applications.
The IEEE standard for it specifies the physical (PHY) and media access control (MAC) layers and the The air interface is Direct Sequence Spread Spectrum (DSSS) using BPSK.

System-on-Chip Considerations
The silicon on chip contains many different features on a single chip like the radio transceiver, data processing unit,memory and user-application features on one single silicon die. The overhead id reduced by the intimate interaction of dedicated on-chip functions. short time-to-market and low manufacturing cost is achieved by:
- Lowest system bill-of-materials
- Small footprint and small number
of components
-Simpler assembly and testing
Easy and reliable design (single
active device)

SoC Design
true system-
on-chip CMOS solutions is provided by the CC2430 family. the globally available 2.4 GHz ISM band is an attractive feature and it allows for flexibil-
ity of application designs.Here, the high performance 2.4 GHz DSSS radio
transceiver design is combined with 8051 microcontroller. Other features are:
-8K bytes RAM
-128K bytes of embedded Flash memory
-integration capability and low cost of CMOS

get the report here:
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