Cellular Phones as Embedded Systems Liza Rodriguez Aurelio Morales EEL Embedded Systems Dept. of Electrical and Computer Engineering University of Florida

EEL 6935 Cellular Phones as Embedded Systems 2 of 33 Outline Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 3 of 33 Outline Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 4 of 33 Cellular Generations oAnalog Cellular Technology (1G)  Early 1980’s  NMT, AMPS (FDMA)  Susceptible to noise and interference. No protection. oDigital Mobile Communication (2G, 2.5G)  Early 1990’s  GSM (TDMA), IS-95 (CDMA), IS-136 (D-AMPS, TDMA), PDC (TDMA)  Data services: SMS  Digital encryption of conversations. Enhanced privacy. oWide Band Mobile Communication (3G, 3.5G)  Early 2000’s  EDGE (TDMA), CDMA 2000, UMTS (CDMA)  Data transfer rates >= 2 Mbit/s  Data & Voice convergence, Internet access. oBroadband Mobile Communication (4G)  LTE Advanced, IEEE (WiMAX)  Data transfer rates >= 100 Mbits/s  Mobile IPTV, Wireless VoIP.

EEL 6935 Cellular Phones as Embedded Systems 5 of 33 Evolution of Radio Systems, Mobility, Data Rates Introduction (cont.)

EEL 6935 Cellular Phones as Embedded Systems 6 of 33 Convergence enables people to create, share and consume digital content, using interoperable devices Cellular phones evolve from traditional cost-optimized handhelds to multifunctional terminals Cellular phones: key platform for mobile convergence applications (web browsing, video streaming, etc.) Digital Convergence Introduction (cont.)

EEL 6935 Cellular Phones as Embedded Systems 7 of 33 Agenda Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 8 of 33 Extremely complex embedded system Functional blocks are custom-made for mobility Chips are either proprietary designs or based on available chips. Miniaturization and functionality Today’s Cellular Phone

EEL 6935 Cellular Phones as Embedded Systems 9 of 33 Block diagram of triple-band cellular phone

EEL 6935 Cellular Phones as Embedded Systems 10 of 33 Example: Blackberry Bold

EEL 6935 Cellular Phones as Embedded Systems 11 of 33 Example: Blackberry Bold

EEL 6935 Cellular Phones as Embedded Systems 12 of 33 Example: Blackberry Bold

EEL 6935 Cellular Phones as Embedded Systems 13 of 33 Example: Blackberry Bold

EEL 6935 Cellular Phones as Embedded Systems 14 of 33 Example: Nokia N95

EEL 6935 Cellular Phones as Embedded Systems 15 of 33 Example: Nokia N95

EEL 6935 Cellular Phones as Embedded Systems 16 of 33 Example: Nokia N95

EEL 6935 Cellular Phones as Embedded Systems 17 of 33 Example: Nokia N95

EEL 6935 Cellular Phones as Embedded Systems 18 of 33 Agenda Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 19 of 33 Development of Cellular phones Miniaturization Functionality

EEL 6935 Cellular Phones as Embedded Systems 20 of 33 Baseband and RF domains challenges ChallengePossible solutionNew Challenges Baseband ASICs are limited in performance by computational power, on- chip communication and clock distribution Decentralized architectures: small distributed controller processors running at lower frequencies Management of processing power resources Baseband flexibility and support for multiple radio systems Use configurable logic, configurable processors, or processor generators Design methodology, verification and testability RF Cost and size of BiCMOS chips RF on digital CMOS technology Substrate-coupling effects, device models RF design portabilityRF on digital CMOS technology New RF circuits and architectures based on fast sampling and time-discrete signal processing needed

EEL 6935 Cellular Phones as Embedded Systems 21 of 33 RF challenges: Multiradio oWide variety of radio systems oCombination of systems at reasonable cost and size oInterference oMiniaturization challenges  Antennas  Filters

EEL 6935 Cellular Phones as Embedded Systems 22 of 33 Outline Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 23 of 33 Memory Challenge Total memory requirement is increasing rapidly Mass Memories – interactive games, high quality video Large memories are required to support data downloading and local storage Supported by external memory cards: MMC or SD Small Memories – processing and small applications Memory chips and their interconnections consume large areas on PCBs and are accessed frequently New types of NVRAM may challenge memory chips to provide smaller and more cost effective memory solutions

EEL 6935 Cellular Phones as Embedded Systems 24 of 33 NVRAM – Alternatives to Flash Memory Ferroelectric RAM (FeRAM) DRAM cell with ferroelectric dielectric in the storage capacitor Advantages: low power, faster reads and writes (single word vs. entire block erase), greater number of write-erase cycles (10 16 vs ) Disadvantages: lower storage density, higher cost Phase Change Memory Glass cells that become crystalline or amorphous by cooling Advantages: faster reads and writes, greater number of write-erase cycles (10 8 vs ), longer hold times Disadvantages: temp sensitivity, no pre-programming

EEL 6935 Cellular Phones as Embedded Systems 25 of 33 Application Platform Mobile internet – web browsing, video calls and high bit rate streaming Java ME – provides flexible user interfaces, built in network protocols, multimedia support Fact: 2.1 Billion mobile phones use Java platforms 3 rd Party Mobile Applications – if developed in Java, are portable enough to run on almost all cell phones

EEL 6935 Cellular Phones as Embedded Systems 26 of 33 Java – Hardware or Software? Hardware – an additional small processor dedicated for running Java Improves performance, minimizes memory requirements Software becomes dependent on inflexible hardware implementation Software – Java is run on baseband processor Virtual machine – Java commands are interpreted as equivalent microprocessor commands -- slow! Just In Time – compiler that would translate Java classes into processor instructions --- fast!

EEL 6935 Cellular Phones as Embedded Systems 27 of 33 Power Challenge Recent evolution of communication and application functions have substantially increased power consumption Constant annual growth of 10% in battery capacity has enabled battery volume shrinkage while having mAh level constant However, when 3G or WLAN communication is run simultaneously with multimedia applications, power consumption must be reduced

EEL 6935 Cellular Phones as Embedded Systems 28 of 33 Power consumption and Battery Capacity

EEL 6935 Cellular Phones as Embedded Systems 29 of 33 Solutions to Power Gap 10% increase in battery capacity will continue forever Reduce power hungry components: Antennas – Bluetooth, Wi-Fi, RF Digital displays Dynamic voltage and frequency scaling (DVFS) Reconfigurable RF components to reduce the number of ICs.

EEL 6935 Cellular Phones as Embedded Systems 30 of 33 Outline Introduction Introduction Today’s Cellular Phone Today’s Cellular Phone Architecture Challenges for Wireless Access Architecture Challenges for Wireless Access Memory, OS, and Power Challenges Memory, OS, and Power Challenges Conclusions Conclusions

EEL 6935 Cellular Phones as Embedded Systems 31 of 33 Cellular phones have come a long way from analog communication devices to digital mobile computers. Today, a cellular phone is a paradigm of an embedded system having highly optimized cost, size, efficiency and performance. Challenges in RF circuits, implementation architecture, memory, and power consumption are still affecting the development and growth of mobile devices. New technologies such as decentralized architectures, reconfigurable circuits, advanced memories, and low power designs will help overcome challenges. Conclusions

EEL 6935 Cellular Phones as Embedded Systems 32 of 33 References

EEL 6935 Cellular Phones as Embedded Systems 33 of 33 Questions?