无线通信-课程教案.doc

Wireless Communications课程教案山东大学信息科学与工程学院袁东风课程总体介绍：1. 教材：原版引进教材:Wireless CommunicationsStanford university, USA。2. 目前实际教学学时数：共计32学时。3. 教学内容：Chapter 1: Overview of Wireless Communication Systems (2学时) Chapter 2: Path Loss and Shadowing (4学时) Chapter 3: Adaptive Modulation (6学时) Chapter 4: Multiple Antenna Systems (4学时) Chapter 5: Multicarrier Modulation (2学时) Chapter 6: Cellular Systems (4学时) Chapter 7: Ad-Hoc Networks (6学时) Chapter 8: Wireless Metropolitan Area Networks (WMAN) (2学时)Chapter 9: Case Study of Wireless Communication (2学时)课程教案:Chapter 1: Overview of Wireless Communication Systems 1.1 History of Wireless Communications1.2 Wireless Vision1.3 Technical Issues1.4 Current Wireless Systems1.5 The Wireless Spectrum1.6 Standards.In this introductory chapter we will mainly review the history of wireless networks, from the smoke signals of the Pre-industrial age to the cellular, satellite, and other wireless networks of today. We then discuss the wireless vision in more detail, including the technical challenges that must be overcome to make this vision a reality. We will also describe the current wireless systems in operation today as well as emerging systems and standards. The huge gap between the performance of current systems and the vision for future systems indicates that much research remains to be done to make the wireless vision a reality.In section1.1 -History of Wireless Communications, need to learn: 1) The initial wireless networks transmitted information over line-of-sight distances; 2) The telegraph network and later by the telephone; Early radio systems transmitted analog signals; 3) The introduction of wired Ethernet technology in the 1970s steered many commercial companies away from radio-based networking; 4) By far the most successful application of wireless networking has been the cellular telephone system; 5) Commercial satellite communication systems, another major component of the wireless communications infrastructure. In section1.2 - Wireless Vision, need to learn: 1) Wireless network; 2) Smart homes; 3) Video teleconferencing; 4) Wireless video; 5) Wireless sensor;6) Wireless networks enable distributed control systems.In section1.3 - Technical Issues, need to learn: 1) Measurements and models for wireless indoor and outdoor channels; 2) Hardware for low-power handheld computer and communication terminals; 3) Techniques to mitigate wireless channel impairments and to improve the quality and spectral efficiency of communication over wireless channels; 4) Better means of sharing the limited spectrum to accommodate the different wireless application; 5) Protocols for routing and mobility management which support users on the move; 6) An architecture to connect the various wireless sub networks together and to the backbone wireline network; 7) An integrated and adaptive protocol stack for wireless networks that extends across all layers of the OSI model. In section1.4 - Current Wireless Systems, need to learn: 1)Cellular Telephone Systems (Definition, Main characteristic, the development trend; EDGE、HSDPA); 2) Cordless Phones; 3) Wireless LANs (IEEE 802.11, HIPERLAN); 4) Fixed Wireless Access; 5) Paging Systems; 6) Satellite Networks; 7) Bluetooth; 8) Home RF; 9) Mobile Ad hoc Networks (Mobile, Multi-hop wireless network capable of autonomous operation, Proposed protocols); 10) Ultra Wideband (Inherent security, High speed, Inherently co-exists); 11) Wireless Metropolitan Area Network; 12) Other Wireless Systems and Applications.In section1.5 - The Wireless Spectrum, need to learn: 1) Methods for spectrum allocation. (Most countries have government agencies responsible for allocating and controlling the use of the radio spectrum; In the U.S. spectrum allocation by FCC for commercial use and by the Office of Spectral Management (OSM) for military use; Obtain spectrum by auction. Advantage: market-based method, use it adequately. Disadvantage: limit competition, delay the ability to invest in infrastructure, high initial price for the end users; Free band: encourage innovation and low-cost implementation; ITU-T); 2) Spectrum allocations for existing systems.In section1.6 Standards, need to learn: 1) IEEE -Institute of Electrical and Electronics Engineering 2) ETSI-European Telecommunications Standards Institute. Chapter 2: Path Loss and Shadowing2.1 Radio Wave Propagation2.2 Transmit and Receive Signal Models2.3 Free-Space Path Loss2.4 Ray Tracing 2.5 Simplified Path Loss Model2.6 Empirical Path Loss Models2.7 Shadow Fading2.8 Combined Path Loss and Shadowing2.9 Outage Probability under Path Loss and Shadowing2.10 Cell Coverage AreaIn this chapter we will characterize the variation in received signal power over distance due to path loss and shadowing. After a brief introduction and description of our signal model, we present the simplest model for signal propagation: free space path loss. We then describe ray tracing propagation models. We therefore also present some simple generic models with a few parameters that are commonly used in practice for system analysis and “back-of-the-envelope” system design.In this chapter, need to learn: 1) The characteristics of the fading channels. A: Concepts-Large-scale propagation effects or local mean attenuation; Path loss and Shadowing; Small-scale propagation effects or multipath fading; Characterize the variation in received signal power over distance; Ray tracing models; Simplified path loss model; Empirical path loss models; Combined path loss and shadowing model; Statistical multipath channel models; Narrowband fading models; Wideband fading models; MIMO channels Single-directional (SD) models; Double-directional (DD) models; B: Examples; C: Research topics-Measurements and models for wireless indoor and outdoor channels; Techniques to mitigate wireless channel impairments and to improve the quality and spectral efficiency of communication over wireless channels. 2) The impact on the system performances: A: Perfect CSI -Channel capacity, Outage probability, BER performance. B: Imperfect CSI (channel estimation)-Source allocation, Channel capacity, Outage probability, BER performance. C: Relative research topics-The distribution of the received SNR under the given diversity combining technique with perfect CSI or imperfect CSI; Channel correlation in multiple antennas systems; The relative channel parameters affecting the capacity and other performances; The optimal allocation of the information symbols and training symbols to maximize the channel capacity.Chapter 3: Adaptive Modulation3.1 Introduction3.2 System Model3.3 Principle of AMC3.4 Variable-Rate Variable-Power MQAM3.5 The principle of HARQ3.6 Three different types of HARQ 3.7 RCPC and CPC codes3.8 What is hot in research3.9 HARQ in the cross layer design3.10 Cross layer design of AMC-HARQ system3.11 AMC-HARQ in MIMO systemHigh-speed wireless data transmission requires robust and spectrally-efficient communication techniques for flat-fading channels. When the channel can be estimated and this estimate sent back to the transmitter, the transmission scheme can be adapted relative to the channel characteristics. Most modulation and coding techniques do not adapt to fading conditions. These non-adaptive methods require a fixed link margin to maintain acceptable performance when the channel quality is poor. Thus, these systems are effectively designed for the worst-case channel conditions, resulting in insufficient utilization of the full channel capacity. Adapting to the signal fading allows the channel to be used more efficiently, since power and rate can be allocated to take advantage of favorable channel conditions. In section 3.1Introduction, need to learn: 1) What is adaptive?2) Why adaptive? Non-adaptive: worst-case channel conditions, inefficient utilization of the channel.Adaptive: increase average throughput, reduce required transmit power, sufficient use of the channel capacity. 3) How to adaptive?Favorable channel conditions: higher data rates or lower powerChannel degrades: reducing the data rate or increasing power4) First proposed by J. F. Hayes in 19685) Has already been used in cellular systems: GSM,EDGE,GPRS,cdma2000,WCDMA etc.6) Core idea of adaptive transmission: transmission schemes are adapted according to the estimated channel condition that sent back to the transmitter. 7) Purpose:Maintain an acceptable bit error rate (transmission quality); Make a more efficient use of the channel capacity.8) Several practical constraints: Channel estimation; Feed back delay; Hardware constraints In section 3.2System Model, need to learn:Capacity in AWGN，Transmission parameters that can be adapted: data rate (constellation size); coding rate; error probability; transmitted power; or any combination of these parameters.In section 3.3Principle of AMC, need to learn:1) Variable Data Rate Techniques and Example: Modulation schemes in EDGE; EDGE link Throughput. 2) Variable Coding Techniques: Different channel codes are used to provide different coding gain to the transmitted bits; Constraints; Implementation. 3) Variable Error Probability: Adapt the instantaneous BER subject to an average BER constraint. 4) Information Theory Basis - Capacity of AWGN Channel; Capacity of Flat-Fading Channel; Capacity of Fading Channel with Power Control; Optimal power adaptation; In section 3.4Variable-Rate Variable-Power MQAM, need to learn:1) Emphasis: Practical adaptive modulation methods, spectral efficiency relative to the theoretical capacity.2) Design methods;3) Principle of VRVP MQAM ; 4) Principle of VRVP MQAM-with the constellation restriction.5) AMC with LDPC Codes In section 3.5The principle of HARQ, need to learn:1) FEC(forward error control) + ARQ(automatic repeat request) = HARQ(hybrid automatic repeat request)2) FEC: error-correction code (channel code: convolutional code, turbo code, low density parity code (LDPC), space time code), high efficiency ARQ: error-detection code (CRC (cyclic redundancy check), parity check), high reliability3) HARQ: use the error-correction code to correct the errors induced from the noisy channel, use the error-detection code to check whether the information is decoded correctly, if not, initiate the retransmission.4) The Framework of HARQ. In section 3.6Three different types of HARQ , need to learn:1) The Type-I HARQ2) The Type-II HARQ3) The type-III HARQIn section 3.7RCPC and CPC code, need to learn: Example of RCPC code; Example of the CPC code.In section 3.8What is hot in research, need to learn:1.Improving turbo codes through code design and hybrid ARQ 2.Reliability-based hybrid-ARQ using convolutional codes 3.Hybrid automatic repeat request schemes using turbo codes and low-density parity check codes 4.Performance of punctured space-time codes over wireless channels and their application 5.Packet combining and adaptive erasure processing in wireless spread-spectrum packet data networks Cross-layer design for retransmission protocols in wireless networks6. Reliability-based hybrid ARQ and rate-compatible punctured convolutional (RCPC) codesIn section 3.9HARQ in the cross layer design, need to learn:1) Purpose: combine the Adaptive Modulation and Coding (AMC) at the physical layer and the Hybrid Automatic Repeat reQuset (HARQ) at the data link layer.2) Qos: determine the AMC range under the prescribed time delay and the packet error rate at the data link layer3) AMC: use AMC scheme defined in the 802.11a and hiperlan/2 .4) HARQ: use type-I HARQ and type-II HARQ (IR)5) Framework of the cross layer design6) Some results of the type-I HARQ in the cross layer design and the analysis of the results above.In section 3.10Cross layer design of AMC-HARQ system, need to learn:1) System model2) Principle of AMC-HARQ- QoS Constraints3) AMC Design at the Physical Layer4) AMC-HARQ based on LDPC CodesIn section 3.11 AMC-HARQ in MIMO system, need to learn:1) System model2) Principle of AMC-HARQ in MIMO3) Results of Average spectral efficiency versus average SNR for different u.Chapter 4: Multiple Antenna Systems4.1 Multiple Input Multiple Output (MIMO) Systems4.2 Space-time Codes4.3 Smart Antennas4.4 Researches on Multiple Antenna Systems4.5 Introduction to MIMO Test-bedMultiple antennas at the transmitter and/or receiver of a mobile system can increase data rates and performance (multiple input multiple output systems) or reduce ISI and interference from other users (smart antennas). In this chapter we treat both of these techniques and discuss the performance improvement that can be achieved via each technique.In section 4.1Multiple Input Multiple Output (MIMO) Systems, need to learn:1) Introduction of MIMO Systems:What is MIMO? Why MIMO?2) The Narrowband Multiple Antenna System Model3) Transmit Precoding and Receiver Shaping: Precoding concept, Shaping formula4) Parallel Decomposition of the MIMO Channel: Theory analysis and derive.5) MIMO Channel Capacity: Water-filling power allocation 6) Beamforming: Why beamforming? MIMO Channel with Beamforming; Beamforming criterion. In section 4.2Space-time Codes, need to learn:1) Concept of Space-time coding: is just coding and modulation in MIMO systems 2) Main Space-time Codes: Space-Time Block Code (STBC). Space-Time Trellis Code (STTC) Layered Space-Time Code (LST).3) An Example of Space-Time Codes: Alamouti Space-Time Block Code4) Researches in Our Lab: MMSE group detection Adaptive power allocation Combine ML-STTC and adaptive rate channel coding A closed form space-time transmission scheme based on SVD of channel matrixIn section 4.3Smart Antennas, need to learn:1) Antenna array combined with signal processing in both space and time.2) Reduce cochannel and multipath interference by direction of arrival (DOA) estimation.3) Advantage: range extension, capacity enhancement, higher data rates and better BER performance .4) Structure of Smart Antennas.5) Different Smart Antennas: switched beam antenna, adaptive array antennaIn section 4.4Researches on Multiple Antenna Systems, need to learn:1) Space-Time Coding in MIMO Systems2) Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) 3) Blind Signal Processing In MIMO Systems4) Smart AntennaIn section 4.5Introduction to MIMO Test-bed, need to learn: MIMO algorithms are mostly tested by numerical simulation in PC, lacking of good channel model neglecting many factors in realization (e.g., nonlinearity, synchronization error )We need a way to verify all of these algorithms by measurements over a real air interface.1) Existing Testbed: MIMO WCDMA transmission for 3G telephone systems (by Lucent Technologies); MIMO OFDM transmission for 4G telephone systems (by ETRI, Korea); A MIMO testbed was set up by utilizing Sundance components for baseband processing and Atmel RF components ( University of Duisburg, Germany). These prototypes and testbeds were very expensive, initial realizations of a special research idea or standard, nowadays mostly testbeds are used in research. Some platfroms focus on off-line approach2) Our Non-realtime Testbed Concepts: Our testbed resembles the existing examples and extends them by an easy to use Matlab to allow for a multitude of experiments with very different constraints. Researchers without hardware and software background knowledge can use our testbed easily, the algorithmic designer can focus on digital baseband data processing by using MATLAB on his own PC. The system designers (hardware and software) can use these testbed to verify their new idea quickly , thus their design risks are reduced . Our testbed is not developed for a single type of experiment or signal, which means that there is no need to redesign parts of the design or signal processing in order to allow several researchers and research teams to share the same expensive testbed hardware for dierent experiments.Chapter 5: Multicarrier Modulation5.1 Data transmission using multicarriers 5.2 Multicarrier modulation with overlapping subchannels5.3 Orthogonal Frequency Division Multiplexing 5.4 OFDM AccessThe basic idea of multicarrier modulation is to divide the transmitted bitstream into many different substreamsand send these over many different subchannels. Typically the subchannels are orthogonal underideal propagation conditions, in which case multicarrier modulation is often referred to as orthogonal frequency division multiplexing (OFDM). The data rate on each of the subchannels is much less thanthe total data rate, and the corresponding subchannel bandwidth is much less than the total system bandwidth. The number of substreams is chosen to insure that each subchannel has a bandwidth lessthan the coherence bandwidth of the channel, so the subchannels experience relatively flat fading.Thus,the ISI on each subchannel is small. Moreover, in the discrete implementation of OFDM, often called discrete multitone (DMT), the ISI can be completely eliminated through the use of a cyclicprefix. The subchannels in OFDM need not be contiguous, so a large continuous block of spectrum is not needed for high rate multicarrier communications. In section 5.1Data transmission using multicarriers, need to learn:1) Background: Future wireless systems are