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 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.
The Z-Wave technology is available in the Z-Wave Single Chip solutions. The Z-Wave protocol stack is embedded in the chips, and 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 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:
c. 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.
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 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 -€œ 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.
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.
1. Nodes that need to initiate communication with a large amount of nodes are based on one of the
2. controller protocol stacks.
3. Nodes that only need to initiate communication with a well-defined subset of nodes are based on
4. one of the routing slave protocol stacks.
5. Nodes that do not need to initiate communication, but only need to react to communications
6. 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 Ëœalways 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.
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.
a typical mesh network with a solid line illustrating the communications path between two nodes, which are beyond direct communication range.
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.
A typical home control network is installed and managed by the homeowner. This imposes a strong Ëœease of use-„¢ requirement on the network protocol. Four fundamental elements must be addressed from an Ëœease-of-use-„¢ viewpoint:
Easy network installation
Intuitive authentication/identification of nodes
Zero management of the mesh network
Robust routing protocol
Easy association process
Self-configuration of the associations between nodes
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 Ëœplug& 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 Ëœplug & play-„¢ installation has severe identification problems in the installation process where many devices are installed at the same time-€œ which light 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 .
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 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.
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 .
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 Ëœlistening-„¢, 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 (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.
It is important that RF link fluctuations do not generate errors in the home control network -€œ 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.
In Z-Wave the self-healing functionality covers two main areas:
• 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.
A. Provide an Association Wizard, which guides the user through all necessary decisions.
B. Sanity check of requested association
In Z-Wave the self-association process builds on the basic Z-Wave Ëœnodeinfo-„¢ frame and standardized command definitions, which enables all nodes to present their supported capabilities in a standardized manner and pair if relevant.
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 all functionalities are identical in two products -€œ 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
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-€ž-¢ delivers the optimal balance of the following mass-market requirements:
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 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.
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
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
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.
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.
Optimized 8051 MCU & RF Transceiver
Low cost for use in mass market products
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.
The ZW0102 Z-Wave-€ž-¢ 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.
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
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:
A. RF transceiver
B. RF front-end
E. System crystal
In order to provide a mass-market solution the following considerations must be taken into account when designing the RF platform:
• Power Consumption
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.
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.
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.
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 -€œ 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.
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.
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.
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. 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.
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.
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.
Approximately 100 feet (or 30 meters) assuming "open air" conditions, with reduced range indoors depending on building materials, etc.
The Z-Wave Radio uses the 900 MHz ISM frequency bands. 908.42 MHz in the US 868.42 MHz in Europe.
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.