Wireless Network vs. ASIC

1. Wireless Network vs. ASIC University of Tehran Department of Electrical and Computer Engineering ASIC Course – Spring 2006 Instructor: Dr. S. M. Fakhrai Presented by: Mohammad Ali Tootoonchian This is a class presentation. All data are copy righted to respective authors as listed in the references and have been used here for educational purpose only

2. Outline • Wireless Network Overview • Wireless Network vs. ASIC Issues • Low Power ASIC Design for Sensor Network • Wireless Network Implementation vs. Codesign • ASIC Application in Wireless Network • Conclusion • References

3. Wireless Network Overview[8] • WLAN : Wireless Local Area Network • Wireless Sensor Network • WMAN: Wireless Metropolitan Area Network • WPAN: Wireless Personal Area Network • WWAN: Wireless Wide Area Network Figure1: Wireless Protocol Area Coverage[4]

4. Wireless Network Overview Figure2: Wireless Protocol Application [4]

5. Low Power Design in Wireless Sensor Network • WiseNET: An Ultralow-Power Wireless Sensor Network Solution [1] • Introduction • Network Architecture • WiseMAC Protocol • Wireless Network Architecture • Reducing Power Consumption • Hardware and Software Codesign • WiseNET Node Architecture

6. Low Power Design in Wireless Sensor Network • Introduction • Consists of many energy-autonomous micro-sensors • Sensor Node Characteristics • Monitors local environment, • Locally processing and storing the collected data • Not require maintenance. • Long Lifetime ranges Figure3: Sensor Node Architecture[5]

7. Network Architecture: WiseMAC Protocol • Reducing power consumption requires optimization across all layers • This solution consumes about 100 times less power • Preamble Sampling

8. Network Architecture: Wireless Network Architecture • The infrastructure mode • Mobile nodes communicate through base stations • Particularly its relative simplicity. • Base stations do not have power restrictions. • The ad hoc mode • There is no base station infrastructure. • Successive hops transport a packet. • Higher versatility and potentially lower power consumption. • Can be deployed quickly and in remote areas. • Hybrid Mode

9. Network Architecture: Wireless Network Architecture Figure4: Infrastructure Wireless[6] Figure5: Ad hoc Network Wireless[6]

10. Network Architecture: Reduce Power Consumption • Reduce Power Main Techniques • nodes remain sleeping until they need to undertake a specific task. • An external event also can trigger this wake-up • With Proper design, communication will decrease network power consumption significantly • Power Consumption Factors • Idle listening • Overemitting • Overhearing • Collisions

11. Hardware Software Codesign and Power Reduction • Design the radio and protocol concurrently. • Power consumption in receive and transmit mode • Wake-up time • Bit and frame synchronization time • The presence of an receive signal strength indicator • Some way to filter incoming packets • The time to switch from receive to transmit mode or vice versa • Receiver sensitivity and maximum transmit power • The capacity to adjust transmit power and receiver sensitivity • Power consumption in sleep mode with a running, accurate clock

12. Hardware Software Codesign • Basic Issue • Minimize the transmit power • Because nodes usually transmit rarely, the transmit energy is not the most important parameter to be optimized. • Reducing energy consumption and wakeup time in receive mode. • We added robust bit synchronization and packet filtering based on a programmable pattern • Developed a complete sensor node SoC

13. Hardware Software Codesign Figure6: Generic WiseNET SoC building blocks. In addition to the ultralow-power dual-band radio transceiver (TX and RX), the architecture includes a sensor interface with a signal conditioner and two analog-to-digital converters (ANA FE), a digital control unit based on a Cool-RISC microcontroller (μC) with on-chip low-leakage memory, several timebasis and digital interfaces, and a power management block (POW). [1]

14. WiseNET Node Architecture • long-term autonomy and low average power consumption. • Tiny to fit into all kinds of spaces and, given their high number • Inexpensive • SoC approach to design • Highly integrated devices • Dedicated integrated circuit.

15. WiseNET Node Architecture • Design Objective • Keep the power consumption within the 1-milliwatt range while in receive mode • Achieve several years of autonomy by operating from a single 1.5-V AA alkaline battery • Use a 0.18-micrometer standard digital CMOS process that has no precision analog components • Minimize both the number of external components and the cost.

16. Figure7: The WiseNET SoC sensor node. Key SoC components include the dual band transceiver (RX/TX), the sensor interface with two ADCs (ANA), the power management block (POW), the control unit (μC) with an 8-bit CoolRISC processor, and the embedded low leakage memory (RAM). [1]

17. Wireless Network Implementation vs. Codesign • HW/SW Codesigned Implementation of IEEE 802.16 TDMA MAC for the Subscriber Station [2] • Introduction • Network Architecture • SS Operation • SS MAC function component • Hardware and Software Codesign • Implementation

18. Wireless Network Implementation vs. Codesign • Introduction • IEEE 802.16 MAC Subscriber station (SS) • Send upstream packets in the uplink duration • Scheduling information specified by the Base Station (BS) • Time-critical job needs to be implemented in HW • No timing constraints can be guaranteed in SW. • An important factor to guarantee performance of high-speed protocol is integration between software (SW) and hardware (HW).

19. Network Architecture: SS Operation • The BS assigns the radio channel to each SS • According to the scheduling policy of the medium access control (MAC). • Request/grant mechanism to coordinate transmissions among multiple SSs.

20. Network Architecture: SS MAC Component • The Service Specific Convergence Sublayer (CS) • Provides any transformation or mapping of external network data to the MAC Common Part Sublayer (CPS). • The Privacy Sublayer • Pertains to authentication, secure key exchange, and encrypting. • The MAC CPS responsible of • System access, • Bandwidth allocation, • Connection establishment, • Connection maintenance. • Receives data form the various CSs, through the MAC SAP, • Classified to particular MAC connection (associated with Connection Identifier). • The heavy loaded jobs are as follows. • Framing: Fragmentation/Packing • Automatic repeat request(ARQ): Selective-Repeat is assumed • Encryption : DES algorithm is assumed. • CRC-32 • Uplink Scheduling

21. Hardware and Software Codesign • The important criteria for partitioning • SS has to be as fast as it is able to satisfy the timing request • Implementation complexity and the memory in the downlink transmission • Implementation Methodology: • A functional specification, • System-level partitioning, • Communication synthesis, • Virtual prototyping and implementation. • The validation was performed using C description • The basic idea of codesign is that the behavior of a complete system should be described abstractly in a uniform manner,

22. Implementation • MAC board will be interfaced with laptop computer using PCMCIA interface (VHDL) • MAC board contains • StrongARM SA-1110 processor operated by Montavista Linux, • SW implementation codes are developed as loadable kernel module, • Single Xilinx VirtexTM-II FPGA • HW implementation codes are written by VHDL.

23. Implementation Figure8: HW/SWfunctional partitioning and architecture of MAC board [2]

24. ASIC Application in Wireless Network • A design and implementation of ASIC for high-quality VoIP terminal over wireless LAN[3] • Introduction • VoIP Architecture • ASIC Design • ASIC Implementation

25. ASIC Application in Wireless Network • Introduction • The lower quality of VoIP service compared with circuit-based network is an open problem to be solved for the wider applications of all IP networks. • For the enhancement of quality of voice for VolP applications, • Wideband speech codec technology was the first consideration for better quality of media source itself.

26. VoIP over Wireless LAN Architecture • The features of G.729EV provide. • G.729EV is bit-level interoperability with legacy G.729 core codec, • Frame size of G.729 is very short as 10ms • It gives the easier interoperability with the mobile phone. • Its scalability for the capacity of terminals and bandwidth.

27. VoIP over Wireless LAN Architecture Figure8: Overall architecture of ASIC [3]

28. ASIC Design • ASIC Characteristics • High-performance RISC core with DSP features • not the use of additional DSP core as shown • 16-channel DMA Controller • for transferring data at high speed, • Interrupter Controller, • AHB I/O decoder, • CLCD Controller, • Reset and Clock Controller, • Elastic Buffer, • APB (Advanced Peripheral Bus), • Timers • Free Running • Periodic Timer

29. WMAC Implementation • WMAC QoS • The excessive packet delay and loss between AP and terminal. • IEEE8O2.1lie standard provides 1 solution by using the differentiated queue management with priority based on class of service. • WMAC Design • PLCP interface, • Interrupt control and • Management part • Processes management data of WMAC and WPHY. • Data transmission part • Transmit controller, • Transmit FIFO, • Transmit data pump, • Data multiplexer, • Data reception part includes • Receive controller, • Receive FIFO, • Receive data pump • WMAC Codesign

30. ASIC

31. Conclusion • Nowadays Wireless Protocol play a main role in communication world industry. • Based on protocol specification, developed application and specific constraint design attributes change significantly • Power • Time • Area • Bandwidth • Signal Integrity • Codesign goals and objective should be satisfy protocol specification, application request and user constraints. • ASIC Design and implementation

32. References • Papers [1]:”WiseNET: an ultralow-power wireless sensor network solution”; Enz, C.C.; El-Hoiydi, A.; Decotignie, J.-D.; Peiris, V.;Computer Volume 37,  Issue 8,  Aug. 2004 [2]:”HW/SW codesigned implementation of IEEE 802.16 TDMA MAC for the subscriber station”; Nak Woon Sung;Computer and Information Science, 2005. Fourth Annual ACIS International Conference on 2005 [3]:”A design and implementation of ASIC for high-quality VoIP terminal over wireless LAN”;Do Young Kim; Jong Won Park;Advanced Communication Technology, 2006. ICACT 2006. The 8th International Conference Volume 3,  20-22 Feb. 2006 • WebSites: [4]:http://www.eurecom.fr/~nikaeinn/adhocNetworks/Wireless_Technologies.pdf [5]:http://www.isoc.org/pubs/int/cisco-1-1.html [6]:http://www.crc.ca/en/html/crc/home/mediadesk/eye_on_tech/2005/issue2/devices_that_sense [7]:http://www.merl.com/ projects/sensornet/ [8]:ttp://www.tutorial-reports.com/