You can’t make it if you can’t test it, so the saying goes. That is nowhere more true than in the case of a broadly interoperable technology like wireless communications. On the heels of the initial release of the long-term evolution (LTE) wireless standard, Agilent Technologies Inc. produced LTE and the Evolution to 4G Wireless: Design and Measurement Challenges, a detailed text on the test and evaluation challenges involved in the move to LTE. Four years have passed since that time, during which the standard has evolved dramatically, especially with the introduction of LTE Advanced (Release 10). In response, Agilent has updated the book, adding over 180 pages of material on carrier aggregation, over-the-air (OTA) testing and non-signaling test methods aimed at manufacturing. It’s an essential text for engineers designing, testing, and manufacturing compliant devices and systems. We’re delighted to present an excerpt from LTE and the Evolution to 4G Wireless: Design and Measurement Challenges, 2nd edition, courtesy of Agilent Technologies and John Wiley & Sons; for a 20% discount off cover price, enter VBD11 at checkout.
The new standard provides handset manufacturers and carriers alike with a range of choices to satisfy consumer demands. That makes the design and manufacturing process harder, though, not easier, says Moray Rumney, Lead Technologist, Technical Leadership Organization at Agilent Technologies, and editor of the book. He sits on the 3GPP radio access network (RAN) working group 4 (WG4), which is responsible for developing the air interface standard for HSPA+ and LTE-Advanced. “The modern smartphone will be a “multi” device: multi-format, multi-band, multi-carrier and multi-antenna,” he says. “In each dimension there are many possibilities, and the combination of all four lead to a highly complex device with many previously unseen radio challenges. Making the right choices and maintaining performance within a cost-effective design has never been harder.”
The development of LTE-Advanced is far more than just a simple upgrade from LTE. “The combination of advanced MIMO with carrier aggregation creates an exponential increase in device complexity that will require difficult trade-offs to be made,” says Rumney. The specifications now define 51 CA combinations, for example, each of which requires unique device design in terms of filtering, switching and testing. Software defined techniques may exist at baseband to accommodate all the radio permutations, but these techniques do not extend to the power amplifiers, duplex filters, switches and antennas. There, custom RF design is still required, and the challenges abound. “Since there is limited space, tough decisions will need to be made when choosing the bands, band combinations and MIMO configurations which any particular UE will support,” he continues. “Each unique device will need to undergo long and costly conformance testing so there is a direct conflict between ease and cost of design vs. the flexibility of the end product. This book helps explain the underlying test and measurement issues that will shape the design choices that need to be made.”
Below, you’ll find the table of contents for the book, as well as an excerpt on beamforming.
Table of contents Chapter 1 LTE Introduction 1.1 Introduction 1.2 LTE System Overview 1.3 The Evolution from UMTS to LTE 1.4 LTE/SAE Requirements 1.5 LTE/SAE Timeline 1.6 Introduction to the 3GPP LTE/SAE Specification Documents 1.7 References
Chapter 2 Air Interface Concepts 2.1 Radio Frequency Aspects 2.2 Orthogonal Frequency Division Multiplexing 2.3 Single-Carrier Frequency Division Multiple Access 2.4 Multi-Antenna Operation and MIMO
Chapter 3 Physical Layer 3.1 Introduction to the Physical Layer 3.2 Physical Channels and Modulation—Mitsuru Yokoyama, Bai Ying 3.3 Multiplexing and Channel Coding 3.4 Introduction to Physical Layer Signaling 3.5 Physical Layer Procedures 3.6 Physical Layer Measurements and Radio Resource Management
Chapter 5 System Architecture Evolution 5.1 Requirements for an Evolved Architecture 5.2 Overview of the Evolved Packet System 5.3 Quality of Service in EPS 5.4 Security in the Network 5.5 Services
Chapter 6 Design and Verification Challenges 6.1 Introduction 6.2 Simulation and Early R&D Hardware Testing 6.3 Testing RFICs With DigRF Interconnects 6.4 Transmitter Design and Measurement Challenges 6.5 Receiver Design and Measurement Challenges 6.6 Receiver Performance Testing 6.7 Testing Open- and Closed-Loop Behaviors of the Physical Layer 6.8 Design and Verification Challenges of MIMO 6.9 Beamforming 6.10 SISO and MIMO Over-the-Air Testing 6.11 Signaling Protocol Development and Testing 6.12 UE Functional Testing 6.13 Battery Drain Testing 6.14 Drive Testing 6.15 UE Manufacturing Test
Chapter 7 Conformance and Acceptance Testing 7.1 Introduction to Conformance Testing 7.2 RF Conformance Testing 7.3 UE Signaling Conformance Testing 7.4 UE Certification Process (GCF and PTCRB) 7.5 Operator Acceptance Testing
Chapter 8 Looking Towards 4G: LTE-Advanced 8.1 Summary of Release 8 8.2 Release 9 8.3 Release 10 and LTE-Advanced 8.4 Release 11 8.5 Release 12
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.