Z - Wave report

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Z-WAVES

INTRODUCTION

Z-WAVE AS HOME CONTROL RF PLATFORM

In recent years wireless home control products like light switches, thermostats,

blinds/drapes, appliance controls, energy management and access controls have

reached the market. In order to have a true mass-market for home controls, it is

important to have a low cost technology, which is easy to install and operate. This

requires a lightweight system, which, from the end-user or installer point of view, is

easy to install and requires no ongoing network management.

The network must be a self-organized mesh network, ensuring error free

communication and, in the case of malfunction, using self-healing mechanisms to re-

establish a reliable network. To support a full home control system, the technology

must be designed to support horizontal applications, enabling different product types

from various vendors to communicate with each other and use each others

functionality (for example a movement sensor turns on a light switch).

In order to reach low cost points, the RF platform must be highly integrated,

manufactured in low cost processes and the associated software protocol must be very

lightweight. From a product developer’s point of view, it is important that the

development and manufacturing of products based on the technology is simple. The

physical modules must have a small form actor, enabling easy integration into new

and existing home control products.

Today, home control products are often developed and manufactured in low

salary countries to keep the cost to a minimum. It is therefore a significant schedule


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accelerator to be able to deliver the RF module as a premanufactured and pre-tested

“component”.

An exciting new technology has finally arrived is the Z-Waves which uses

RF signals to send the communication messages between modules. The RF signals

can travel at least 100 feet and each module also acts as an amplifier for the signal and

rebroadcasts it out.

Z-Wave™ is a wireless RF-based communications technology designed for

residential and light commercial control and status reading applications. Z-Wave

transforms any stand-alone device into an intelligent networked device that can be

controlled and monitored wirelessly. Z-Wave delivers high quality networking at a

fraction of the cost of other similar technologies by focusing on narrow bandwidth

applications and substituting costly hardware with innovative software solutions.

ded in the chips, aThe Z-Wave tmbedechnology is available in the Z-Wave

Single Chip solutions. The Z-Wave protocol stack is end Flash memory is available to

the manufacturer/OEM for their application software. For smooth product

development, a range of manufacturing blueprints of the PCB circuitry surrounding

the Z-Wave Single Chip is offered - including antenna circuitry and filters.

Z-Wave is also compatible with HomeSeer, HAL2000, and the Elk M1

Automation Software. Z-Wave can also co-exist with existing X10 hardware in a

HomeSeer/HAL2000/Elk environment.

This paper describes how the Z-Wave Technology addresses the needs of the

home control network, product development, and manufacturing processes.

HOME CONTROL APLICATIONS

The number of interesting home control applications is vast, ranging from simple

remote control of light to sophisticated comfort and surveillance systems which use

many different resources in the home. The applications can be divided into a number


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of categories: Comfort Enhancement, Energy Management, Access Control and

others.

Comfort Enhancement: A futuristic example would be that, when entering the living

room, the drapes go down, the lights dim to a comfortable level, the stereo turns on

and your favorite music is played - all initiated by a push on a button or even a sensor

detecting your entrance into the room.

Energy management: enables you to save money and improve the environment by

turning off the light and turning down the heat in rooms which are not occupied,

turning off all the lights when the house is empty, switching off the heater/radiator

temporarily while the window is open, and so on.

Access control: enables you to ensure that all windows/doors are closed and

appliances such as irons or coffee makers are switched off before you leave the house.

Additionally sensors can detect an intruder entering the home and initiate a series of

events such as turning on the light, activating a web cam and sending a message to

your mobile phone.

HOME CONTROL TCHNOLOGY CONSIDERATIONS

When designing a home control technology three main requirements must be taken

into account:

• Ease-of-use

• Reliability

• Low cost

Ease-of-use: When designing a wireless home control technology for the mass-

market it is very important to realize that it is the average homeowner or a semi-

skilled installer who typically installs the system. The technology must provide simple

intuitive installation and require no network management by the user during the

lifetime of the installation. Finally the technology must be designed to support

horizontal applications; enabling different product types from various vendors to

seamless communicate with each other and use each other’s features.


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Reliability: Robust and reliable RF communication is crucial in order to allow the

home control system to handle sensitive operations. For example, if the home owner

instructs the central door locking application to lock and arm the alarm system, he or

she must be guaranteed that the instruction is registered and executed. Furthermore, as

RF operates on a shared medium, and RF is sensitive to changes in the environment,

protocol algorithms must be applied to make the RF link as reliable as a wired system.

The implementation of this robustness includes features such as frame

acknowledgment, collision avoidance, random back off algorithms, retransmission,

and routing, to achieve reliable links and full home network coverage.

Low Cost: In order to have a true mass-market technology the physical wireless

platform must have a very low cost. The right tradeoffs between technology choice

and cost must be taken without compromising the reliability of the network. As many

home control products are both developed and manufactured in low salary countries it

is important to supply a hardware(HW) and software (SW) platform, which can be

integrated without having significant RF and mesh network knowledge. This can be

accomplished by supplying a ready-to-use and pre-tested HW module and a well-

tested protocol stack, which provides a simple and intuitive interface between the

protocol SW and the application SW. Home control products already exist today,

including wireless control and monitoring of lighting, thermostats, movement sensors,

air conditioning, using “ready-to-use” RF platforms containing both hardware and

software .

The RF platform contains microprocessor, memory, RF transceiver, RF front-

end and system crystal. The SW protocol assures that the products can communicate

with each other in a standardized way. To meet the complex design requirements of

simultaneously achieving low cost, ease-of-use and high reliability the entire wireless

platform development process from protocol and module specification to final

production must be taken into account.

HOME CONTROL PROTOCOL REQUIREMENTS

The home control protocol needs to address and support the required:

Network traffic pattern

Network flexibility


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Network reliability

Network ease-of-use

NETWORK TRAFFIC PATTERN

A home control network is characterized by relatively few nodes (20-200)

within a 150-600m2 area in which each node communicates relatively infrequently –

every 5-15 minutes. A typical communication consists of 4-6 bytes of payload (i.e.

turn on, set dim level, read temperature, read door status etc.). Additionally the

majority of home control applications have relaxed latency requirements of 200ms or

above. The infrequent traffic, in conjunction with the latency requirements, is served

with a network bandwidth of 9.6 kbps.

NETWORK FLEXIBILITY

A home control network consists typically of a complex mix of AC powered

nodes, battery operated nodes, fixed positioned nodes, and moving nodes. All nodes

need to communicate with each other seamlessly. The required network behavior of

these node types typically requires too many resources to support them all in one

protocol stack. In figure 1 the multiple Z-Wave protocol stack options are shown.

The illustration shows how efficiently the protocol stacks can be implemented

when performing system partitioning and at the same time maintaining seamless

communication between any of the node types. The Z-Wave technology supports the

full range of AC-powered, battery powered, fixed position nodes, moving nodes and,

potentially, bridging nodes to other technologies, with a range of Z-Wave protocol

stacks. In the Z-Wave technology, nodes are divided in three fundamental node types

(Controllers, Routing Slaves and Slaves), based on their communication behavior. All

node types work seamlessly together and can be mixed in any combination.

• Nodes that need to initiate communication with a large amount of nodes are based

on one of the controller protocol stacks.

• Nodes that only need to initiate communication with a well-defined subset of nodes

are based on one of the routing slave protocol stacks.


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• Nodes that do not need to initiate communication, but only need to react to

communications requests from others nodes are based on a slave protocol stack.

Z-Wave supports moving battery powered devices such as handheld remotes

and moving sensors within each node type. For controller node types the Portable

Controller protocol stack has support for dynamic changes in position. For Routing

Slave node types, the Routing Slave protocol stack has support for re-discovery of

moving nodes within the overall network topology. The controller node type contains

self organization management functionalities, which simplify the installation and

operation of the network. For example: when the system enables a controller to

become a SUC (Static Update Controller) the changes in network topology are

automatically distributed to all relevant nodes in a system by the Static Update

Controller (SUC).The controller node type furthermore contains versatile installation

functionalities, enabling different installation strategies ranging from local to central

installation. For example: when the system enables a SUC to become a

SIS (SUC Id Server) the installation parameters are distributed to all controllers in the

system. If not enabled, only one controller in the system is assigned to install new

nodes. The assignment can be transferred from one node to another during the lifetime

of the system.

The home control technology needs to handle battery-operated nodes with

great power efficiency in order to provide 10 or more years of operation on 2xAAA

batteries. It is therefore important that the protocol can provide an efficient wakeup

sequence such as powering up based on cyclic wakeup timers, transmitting the frame

and returning to sleep mode.

Figure 2 shows how Z-Wave enables power efficient operation of a battery-

operated thermostat communicating with a temperature control system. The

temperature control system is in ‘always listening’ mode. The thermostat wakes up on

a regular basis and reports its temperature, at the same time asking the control system

whether any changes in settings are required.


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Fig 2: Z-Wave Battery Node Support

NETWORK RELIABILITY

In a medium-sized home, two nodes that need to communicate may be beyond

direct communication range. The home control system therefore needs to support a

mesh network structure enabling the two nodes to use other nodes as routing nodes.

Figure 3 shows a typical mesh network with a solid line illustrating the

communications path between two nodes, which are beyond direct communication

range.

Fig 3: Z-Wave Mesh Network


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The mesh network also serves as the basis for the self-healing functionalities.

RF communications links vary over time due to their strong correlation to the physical

environment. For example, when a door open/closes, furniture is are moved, or there

are simply many people moving about, RF links may fail because the environment is

changing. In these situations the self-healing mechanisms in the technology will

automatically reroute the message through other nodes until the message reaches the

destination node.

NETWORK EASE-OF-USE

A typical home control network is installed and managed by the homeowner.

This imposes a strong ‘ease of use’ requirement on the network protocol. Four

fundamental elements must be addressed from an ‘ease-of-use’ viewpoint:

Easy network installation

• Intuitive authentication/identification of nodes

Zero management of the mesh network

• Self organization

• Robust routing protocol

• Self-healing

Easy association process

• Self-configuration of the associations between nodes

Product interoperability

Easy network installation

The main challenge for easy network installation is to balance the requirements for

easy network joining and the requirements for easy identification of the installed

devices. In the literature a number of different network joining philosophies exist,

ranging from full ‘plug& play’ to manual processes with serial number typing. Most

of these philosophies have shortcomings in real life due to the very limited user

interface on the typical home control product with 1-2 actuators and 1-2 indicators.

The full ‘plug & play’ installation has severe identification problems in the

installation process where many devices are installed at the same time– which light


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switch is which? The manual process burdens the user with an input and/or validation

process, which is impossible in many simple systems where the user interface is

minimal. One example of a more optimal balance between network join and

identification is the Z-Wave installation process shown on figure 4.

Fig 4: Z-wave installation

The Z-Wave installation process is very flexible enabling both local and

central installation. The local installation is ideal for small low cost systems (e.g. 5

light remotes + 30 lamp modules), which are installed by the homeowner or an

installer. The basic philosophy of the Z-Wave local installation process is that the user

activates both the node and the controller in order to install the new product. The

activation can be simultaneous or skewed and it can be initiated once or for all new

nodes depending on the installation scenario. The new product sends out a request to

join the network, which is acknowledged by a controller by assigning an ID to the

node. Finally the new node reports back its neighbor list (nodes within direct RF

range) to the controller enabling it to have full network topology information. The

central installation is ideal for complex home control Systems with many different

products and applications, and which are installed by a professional. The basic

philosophy of the Z-Wave Central Installation process is that the Z-Wave technology

enables any controller in the system to include new products to the system in

coordination with the Z-Wave SIS node. The SIS is typically implemented in a PC or

equivalent intelligent device, allowing the installer to have full remote control and

monitoring over all steps


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in the process.

Zero management of the Mesh Network

The central challenge in network management is the fact that the homeowner

generally does not fully comprehend that the product he has installed is a part of mesh

network. It is therefore important that there is no need for network management in the

typical installation. The mesh network must be self-organizing and self-healing.

Self-organizing

In a self-organizing network, nodes are capable of discovering their neighbors

and distributing this information to others automatically. In a self healing network,

nodes are capable of redirecting traffic if parts of the mesh are down. One example of

a self-organizing network is the Z-Wave network shown on figure 5.

Fig 5: Z-Wave Self Organizing Network

In Z-Wave every node discovers its neighbors when they are included in the

network or upon request. This information is automatically be forwarded to the Static

Update Controller (SUC) in the system. The SUC is always ‘listening’, allowing other

nodes to receive/request topology information. In a self-organizing mesh network the

user does not need to consider whether all nodes in the house can communicate

directly with each other or whether they need a router along the way. The routing

protocol in the mesh ensures that all destination nodes can be reached from any

initiator node. In the literature a wide range of routing protocols are described, each

optimized for a given parameter. Some are optimized for handling large networks


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(distributed algorithms), some for speed and yet others for resource usage. Given the

limited number of nodes in a home control network the

Source Routing Algorithm (SRA) is an efficient solution. An SRA provides a good

balance between resources needed in the nodes and network size. In an SRA, the

initiator generates the entire route through the mesh network to the destination and

places this information into the frame header. The route is generated on basis of the

topology information provided by the self-organizing functionality. The individual

nodes in the route will receive the frame, modify the frame header according to the

routing protocol and forward it to the next node in the route. These nodes do not need

to store any topology information, which is a significant advantage in a network with

scarce resources.

Self-healing

It is important that RF link fluctuations do not generate errors in the home

control network – the network must be self-healing.

Figure 6 shows a situation where the communication between garage door and

Lamp A fails due to a stainless steel refrigerator door opening (illustrated by the red

line) and shows how the technology uses the mesh network to automatically reroute

the message using the nodes in the hallway and the foyer to route the frame.

Fig 6: Re-routing through the mesh network

In Z-Wave the self-healing functionality covers two main areas:


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• Fluctuations in the topology map (e.g. fluctuation of communication links). The

routing algorithm receives information from the failing communication and knows

which link was defective in the route. This link is temporary removed from the

topology and anew route is generated.

• Changes in the topology map (e.g. nodes have changed physical position in the

network).The Z-Wave orphan algorithm enables a node to request the Z-Wave SUC

to initiate a new neighbor search to repair the topology map.

Easy association process

An association between two nodes is a pairing of functionality on one node

with functionality on another node (e.g. an activator on a remote controller is paired

with the dimming functionality of a particular light dimmer node). The central

challenge in an easy association process is to make it as simple as possible for the

home owner or installer. Given the typical home control product, which contains a

limited user interface, this requires that the network support self configuration

covering the following elements.

• Provide an Association Wizard, which guides the user through all necessary

decisions.

• Sanity check of requested association

In Z-Wave the self-association process builds on the basic Z-Wave ‘nodeinfo’ frame

and standardized command definitions, which enables all nodes to present their

supported capabilities in a standardized manner and pair if relevant.

Product interoperability

The central challenge in product interoperability is to balance the full

interoperability requirement with the vendor’s requirement to be able to differentiate

in the market place. Furthermore the interoperability requirement should be

reasonably matched to the end user expectation. The average user does not expect that


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all functionalities are identical in two products – however he or she will expect that all

basic functionality is the same or at least behaves logically. Interoperability is the

basis for creating complete home control systems in which different applications from

different vendors work together.

An example of the total interoperability scope of Z-Wave is shown in figure 7.

Fig 7: Total Interoperability scope

Product interoperability requires standardization on two levels:

• Command Level: All commands that can be transferred between nodes must be

standardized.

• Device Level: All products must be members of a Device Class that defines which

of the commands are mandatory, recommended and optional.

This structure allows products to be interoperable with their basic

functionality. In Z-Wave, interoperability is guaranteed by use of the appropriate

Device Class Specification and by the Z-Wave Certification Program. The Device

Class Specification governs standardization on command and device level for all

home control products. The work is carried out in the Z-Wave Alliance ensuring that

all relevant market inputs from Z-Wave partners are injected into the Device Classes.

The certification program ensures that all products, which carry the Z-Wave logo,

have gone through the certification process.

Z-WAVE FEATURES

Z-Wave™ delivers the optimal balance of the following mass-market

requirements:


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Low Cost for Mass Market

To ensure the lowest possible cost, Z-Wave is dedicated to control and status reading

applications, and therefore operates with a bandwidth of just 9.6 kbps. Z-Wave is not

suited for bandwidth intensive applications such as voice/video transfer. Its bandwidth

is tailored to the specific applications for which it was designed - and so is its cost per

node. Innovative protocol handling techniques replace costly HW implementations to

deliver the right price points. Additionally, the implementation in a mixed-signal

single chip ensures the lowest cost points.

Highly Robust and Reliable

Many RF technologies communicate across the public bands. Consequently, the

public bands are crowded with interference, resulting in poor reliability for most RF

technologies. Z-Wave minimizes these "noise and distortion" problems by using

transmission mechanisms such as 2-way acknowledgement, condensed frame formats

and random back-off algorithms, ensuring highly reliable communication between all

the devices in the network.

Full Home Signal Coverage

Most control systems today require physical wire connections to ensure full building

coverage because the range and reliability of most wireless systems is limited. Z-

Wave's dynamic routing principle, integrated into the technology, secures a virtually

unlimited signal range, as each of the Z-Wave devices repeats the signal from one

device to the next. The same routing principle ensures the RF-signals are routed

around radio dead spots and signal reflections thereby securing a highly robust

transmission covering the entire home.

Easy Network Management

Z-Wave is designed to enable automatic network address assignment at installation,

simple inclusion/exclusion of nodes, and simple association/disassociation of nodes to


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one another. These protocol-handling techniques ensure easy installation, expansion,

and management of the Z-Wave control network. Further, each Z-Wave network has

its own unique Network Identifier preventing control problems or interference from

neighboring networks.

Low Power Consumption

Unlike most control systems, Z-Wave's lightweight protocol implementation and

compressed frames helps keep power consumption low. Additionally, Zensys' Z-

Wave single chip solutions enable advanced power saving modes for battery-operated

devices such as thermostats and sensors.

Versatility

Z-Wave is a scalable protocol that was developed with the versatility to include

additional features and applications as well as to connect to other protocols. To ensure

future flexibility, backwards compatibility and expanded applications, Z-Wave

provides multiple feature support by the use of generic command classes and a

variable frame structure as well as by providing a well-defined API for OEM specific

applications.

Z-WAVE SINGLE CHIP SOLUTIONS

ZW0201

The ZW0201 is a complete System on Chip (SoC) and consists of an

integrated RF transceiver, an 8051 microcontroller, flash and SRAM memory storage

and a range of peripherals. The ZW0201 is fully compatible with the 100 Series

systems and can be easily incorporated into existing product lines.

Benefits of ZW0201

Lowest Price:


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The ZW0201 will allow you to cost reduce your products by dollars! The chip

will be priced below $3 when ordered in 100 k quantities. Further the chip has

integrated many external components to also reduce the surrounding component to

about $1 meaning that a product can be Z—Wave enabled by adding less than $4 to

the Bill of Material.

Most efficient:

For battery-operated devices we are extremely pleased to inform you that

ZW0201 has dramatically reduced its power consumption. It is now possible to create

Z-Wave products such as sensors, remotes, door locks, etc. that can run for up to 10

years with 2 AAA batteries.

Smallest in size:

The ZW0201 is a chip that measures 5 x 5 x 0.9 mm and can be integrated on

a module that is not larger than 12.5 x 13.6 mm. As a result Z-Wave products can be

designed more elegantly and easily integrated into small products.

The ZW0201 is specially suited for the Z-Wave protocol stack as depicted below:

Fig 8: ZW0201 compatible protocol stack

ZW0201 FEATURES:

Optimized 8051 MCU & RF Transceiver

Low cost for use in mass market products


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State of the art package form factor, only 5x5x0.9mm

Reliable wireless communication

Very low power consumption

Complies with both Europe and US government regulatory requirements

Future proof and versatile for integration into any product


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ZW0102

The ZW0102 Z-Wave™ Single Chip is an advanced implementation of

Zensys' Z-Wave wireless control networking technology offering a lower cost, lower

power consumption, and smaller form factor solution.

Zensys' Single Chip solution is specially suited for control and status reading

applications including lighting, HVAC, and appliance control, while the optional

security capabilities through HW encryption support and SW authentication/key-

exchange is suited for sensors, alarm systems, automatic meter reading and energy

management systems.

The ZW0102 is a mixed signal chip integrating RF transceiver, Z-Wave

protocol storage and handling, and OEM product application storage and handling in

one single chip. An on-chip 8 bit CPU core handles both the OEM application as well

as the wireless communication protocol. Up to 20k byte of available flash memory

gives the OEM the opportunity to download and run just about any control application

directly on the Z-Wave Single Chip. This eliminates the need for an additional micro

controller and external Flash memory for application code storage.

Zensys provides a range of tools including reference RF circuitry designs and a

comprehensive Developer's Kit to enable rapid OEM development. Complete ready-

to-go application code examples are tailored to the OEM engineer's needs with fast

time-to-market in mind.

ZW0102 FEATURES:

Mixed Signal IC With 8051 MCU Core And RF Transceiver In A Single Chip

Low Cost For Use In Mass Market Products

Reliable Wireless Communication

HW Supported Encryption Capabilities

Future Proof and Versatile For Integration Into Any Product


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HOME CONTROL HARDWARE REQUIREMENTS

In order to have a home control HW platform, which is highly reliable, the

platform must use leading edge technologies throughout, from initial chip design to

final product design. This includes wafer technology, layout methodology, assembly

methodology, and production test.

A minimal RF platform consists of the following blocks:

• RF transceiver

• RF front-end

• Microprocessor

• Memory

• System crystal

The RF platform is illustrated in figure 9.

Fig 9: RF HW platform block diagram

In order to provide a mass-market solution the following considerations must

be taken into account when designing the RF platform:

• Reliability

• Cost


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• Power Consumption

• Size

The overall RF platform must be very low cost because the market for home control

products are very cost sensitive. The power consumption must be very low in order to

support battery lifetimes of10 years or more for typical sensors. The RF

communication must be reliable and the size should be small, as modules will be

integrated into products with a small physical form factor.

The following section describes the individual RF platform blocks in light of

these platform considerations.

Microprocessor platform

The microprocessor platform contains an instruction effective processor

(CPU), various HW interfaces, memory and a wake-up timer. An instruction/power

effective processor assures fast processing time and low power consumption. To

avoid additional chips/circuitry the microcontroller contains as many interfaces (like

ADC’s etc.) as possible to keep the total system cost down. The memory should be as

small as possible and still have room for the protocol and the application SW in order

to keep cost and power consumption as low as possible.

In order to have optimum battery lifetime, power management is of high

importance and requires careful design of the power circuitry of the entire platform.

The power management is an integrated part of the protocol, which means that the

microcontroller can ensure that only the circuitry that needs to be powered is on and

the remaining circuitry is powered down. A low power timer is needed to have the

battery-powered product wakeup as required. Using a standard Real-Clock-Timer

device usually requires more than 20uA of power. Implementing an on-chip wake-up-

timer using only a few microamperes ensures a low power down consumption leading

to 10+ years of battery lifetime.


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A Frame Handler is implemented to reduce the CPU processing time keeping

the power consumption as low as possible. The Frame handler enables the

microprocessor to be powered down and only the RF transceiver to be powered up

when waiting for frames. Only when the transceiver receives a frame for its specific

product is the frame stored, the RF transceiver is powered down, and the

microcontroller is powered up to process the received frame.

RF Transceiver

In recent years, Zensys has integrated the RF circuit VCO tank and loop filter

into the single hip, eliminating the need to implement between 10 and 20 passive

components. Integrating the passive components on die level does require additional

die area, but enables design of high-Q (quality factor) components, reduces

interconnection distances, and makes the system more reliable and immune to

external noise.

In order to achieve long battery lifetimes, the wireless products transmit with

as low power as possible. The RF transceiver has high receiver sensitivity and utilizes

a communication frequency which ensures long range. These requirements are met by

implementing an effective RF receiver and RF front-end integration chip design in

conjunction with an optimal frequency modulation.

The frequency modulation methodology used is also selected with die area

usage in mind. As a general rule, the use of high frequencies leads to shorter RF

communication range. It is therefore an efficient tradeoff for the RF chips to use sub-

Gigahertz license free ISM frequency bands (US: 902MHz-928MHz, EU: 868MHZ –

870MHz) keeping the communication range long, the power consumption low and the

die size small.

Microcontroller & RF Transceiver integration level

Integration of microprocessor, memory, various interfaces, and the RF

transceiver into one single chip not only reduces the overall RF module cost but also

reduces the die area and improves the overall RF performance.


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Module interconnection

Bringing the overall product cost down also implies the ability to deploy the

same RF module in a wide range of products. Using connectors or solder bumps adds

to the overall cost. A good alternative is to implement castellation notches, which are

plated indentations on the side of the PCB. Castellation notches are suitable for

soldering the RF module to the application PCB in a standard reflow soldering

process together with the other surface mounted components. The same module can

be hand soldered if required.

Production testing

When developing and manufacturing a low cost RF platform, the testing of the

individual components and the RF module is of significant importance because testing

time comprises a significant amount of RF module cost. Having a single chip reduces

the die test (wafer test) to only one die per RF module and the few external digital and

RF components can be tested using simple test equipment. The Z-Wave single chip is

designed with comprehensive self-test circuitry to ensure minimum wafer test time.

Z-Wave RF module

With the previously mentioned considerations in mind, Zensys has developed

a single chip that is supplied on a complete RF Module (ZM2102) for easy

implementation into new and existing products.

A block diagram of the ZM2102 is shown in figure 10.

The highly integrated single chip contains all circuitry required to

control/monitor home control products. Due to the high integration level theZM2102

only consists of 15 components including decoupling capacitors, crystal, RF filters,

enabling a module size of 12.5x13.6mm.


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The high integration allows low cost and high reliability.

THE Z-WAVE ALLIANCE

Home control has been the subject of science fiction and futuristic magazine

articles for years. But the reality has been rather disappointing. What home control

systems have been available until now are either too expensive, too difficult to install

and use and too limited in their scope.

The Z-Wave Alliance has changed all of that. It is an open consortium of

leading independent manufacturers who have agreed to build wireless home control

products based on the Zensys' Z-Wave open standard.

Having this standard means every product that bears the Z-Wave mark will

work with all other Z-Wave products, with no special programming, regardless of

who originally manufacturers the item. As a result, total home control has been made

simple, accessible and affordable to consumers everywhere. Not three years from

now. Not next year- today.

The Z-Wave Alliance members lead the home controls market, providing

systems that deliver increased comfort, convenience, safety and security. Z-Wave

based systems are easy to install and use, and allow products from all members to

interoperate seamlessly between multiple applications and multiple vendors.

Currently, more than 125 companies are developing products that incorporate

the Z-Wave technology. These products fall into every conceivable area, from

traditional lighting, temperature, and entry control to home theaters, windows,

window treatments, pool and spa controls, garage door openers, automated meter

reading and more.


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Each product has to pass a stringent conformance test to assure it meets the Z-

Wave standard for complete interoperability with all other devices and controls.

That's the way to carry the Z-Wave identity mark.

Modulation: GFSK

Gaussian Frequency Shift Keying (GFSK) is a type of Frequency Shift Keying

modulation that utilizes a Gaussian Filter to smooth positive/negative frequency

deviations, which represent a binary 1 or 0. It is used by DECT, Bluetooth and

Z-wave devices. For Bluetooth the minimum deviation is 115 kHz.

Range

Approximately 100 feet (or 30 meters) assuming "open air" conditions, with

reduced range indoors depending on building materials, etc.

Frequency band

The Z-Wave Radio uses the 900 MHz ISM frequency bands. 908.42 MHz in

the US 868.42 MHz in Europe.

CONCLUSION

Z-Wave provides a mass-market home control technology, which is low cost,

low power, easy-to-use and reliable. The mesh network Z-Wave system, with its self-

organizing and self-healing features, combined with flexible but simple installation

procedures, provides an easy-to-use network solution. Z-Wave’s versatile and dense

protocol stacks and highly integrated single chip furthermore enables the needed low

cost points without compromising either network reliability or product versatility. The

Z-Wave Device Classes enable product interoperability across applications and

between vendors.

REFERENCES


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1. www.zwavealliance.com

2. www.zensys.com

3. www.z-wave.com

4. Seminar topic from: www.edufive.com/seminartopics


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http://www.edufive.com/seminartopics

http://www.z-wave.com/

Documents

Z - Wave report