原创 [Original]Analyse of Low-rate Wireless Network

[Original] Analyse of Low-rate Wireless  

Network 

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KuangJunBin: If you take interest in this project or have any problem,  please contact me with E-mail.

My E-mail address: geforcefat@gmail.com

Part 1.Overview of IEEE 802 Standards

IEEE 802 refers to a family of IEEE standards dealing with local area networks and metropolitan area networks. The services and protocols specified in IEEE 802 map to the lower two layers (Data Link and Physical) of the seven-layer OSI networking reference model.

Let’s see The IEEE 802 family of standards(table) :

Specialty of Bluetooth、ZigBee and MBWA：

Bluetooth

           i.              designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device.

         ii.              Version 1.2 : 1 Mbit/s ; Version 2.0 + EDR : 3 Mbit/s ; WiMedia Alliance (proposed)  : 53 - 480 Mbit/s

        iii.              globally unlicensed Industrial, Scientific, and Medical (ISM) 2.4 GHz short-range radio frequency bandwidth.

       iv.              Limits : high price of microchip , only no more than 7 nodes of a Piconet(one master不能超过seven slaves)

ZigBee(recommended)

           i.              offer the fundamental lower network layers of a type of wireless personal area network (WPAN) which focuses on low-cost, low-speed ubiquitous communication between devices

         ii.              a 10-meter communications area with a transfer rate of 250 kbit/s. Tradeoffs are possible to favor more radically embedded devices with even lower power requirements. Lower transfer rates of 20 and 40 kbit/s were initially defined, with the 100 kbit/s rate being added in the current revision.

        iii.              unlicensed frequency bands : 868-868.8 MHz、902-928 MHz and 2400-2483.5 MHz.

       iv.              capacity : up to 254 nodes in a master-slave network

         v.              The technology and protocol is intended to be simpler and cheaper than other WPANs such as Bluetooth. Chip vendors also offer the ZigBee software stack

MBWA

           i.              IP roaming & handoff (at more than 1 Mbit/s)

         ii.              New MAC and PHY with IP and adaptive antennas

        iii.              Optimized for full mobility up to vehicular speeds of <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />250 km/h

       iv.              Operates in Licensed Bands (below 3.5 GHz)

         v.              Utilizes Packet Architecture

       vi.              Low Latency

      vii.              Limits : not mature and not popularized

There are other protocols Outside IEEE (table) :

Part 2.SoC solution for 802.15.4

Here is two popular and powerful ZigBee-Compliant platform, with low power Transceiver plus Microcontroller(table) :

Another solution MRF24J40 is provided by Microchip using ZigBee or MiWi protocol.But MRF24J40 must work with a external MCU like PIC family.

KuangJunBin: If you take interest in this project or have any problem,  please contact me with E-mail.

My E-mail address: geforcefat@gmail.com