MeshConnect™ Module Series

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POWER AMPLIFIER

VOICE CODEC

SOFTWARE TOOLS

The orginal MeshConnect module does not incorporate an external Power Amplifier and therefore the RF output port is

connected directly (through matching components) to the RF antenna. As CEL’s IC IEEE 802.15.4 / ZigBee transceiver

already offers the industry’s best link budget at 106 dB, even without an external PA the MeshConnect can maintain

wireless connection over long distance (3,000 ft line-of-sight).

The Extended Range module adds both an PA and LNA to optimize RF performance. The NEC uPG2250 PA enable the

Extended Range module to output up to +20 dBm transmit power. In the receive path the addition of the UPC8233 LNA

boosts the already sensitive receiver up to -103.5 dBm. The Extended Range link budget boasts a very robust 123.5 dBm

enabling a line of sight range over 2 miles.

INTERFACE

The MeshConnect has all major communication interfaces routed from the IC to the module edge connectors:

• UART1 & UART 2

• SPI

The MeshConnect IC includes three voice codec algorithms: μ-law, a-law and ADPCM.

The μ-law algorithm is a companding algorithm primarily used in the digital telecommunication systems of North America

and Japan. As with other companding algorithms, its purpose is to reduce the dynamic range of an audio signal. In the

analog domain this can increase the signal-to-noise ratio (SNR) achieved during transmission and in the digital domain, it

can reduce the quantization error (hence increasing signal to quantization noise ratio). These SNR improvements can be

traded for reduced bandwidth and equivalent SNR instead. The a-law algorithm is a standard companding algorithm used in

European digital communications systems to optimize/modify the dynamic range of an analog signal for digitizing.

The a-law algorithm provides a slightly larger dynamic range than the μ-law at the cost of worse proportional distortion for

small signals.

Adaptive DPCM (ADPCM) is a variant of DPCM [Differential (or Delta) pulse-code modulation] that varies the size of the

quantization step, allowing further reduction of the required bandwidth for a given signal-to-noise ratio. DPCM encodes

the PCM values as differences between the current and the previous value. For audio applications this type of encoding

reduces the number of bits required per sample by about 25% compared to PCM.

CEL offers complete SW tools for MeshConnect that customers need to create their ZigBee application.

PROFILE BUILDER

• Profile Builder allows for easy creation of custom ZigBee profiles for use in end-user applications.

• Uses the input requirements to modify a set of ‘C’ source files which include the necessary ZigBee functions.

• Output files will contain the ZigBee Device Object (ZDO) descriptors and the ZigBee Device Profile (ZDP) descriptors.

• The ZDO and ZDP define the ZigBee node and functionality.

The output files can be seamlessly integrated with the CEL ZigBee stack libraries.