The Top Ten CommsDesign Articles of 2011

We featured some really great articles on CommsDesign last year. For those of you that contributed articles—whether or not they were in the Top Ten for the year—thank you! You’ll note that several of the articles that made the Top Ten of 2011 list are tutorial in nature. If you are a guru in a specific segment and want to share your knowledge/expertise with the rest of us by way of a tutorial, please let me know.

So, here they are, 1-10 of the top articles for the year. You will see that some of them weren’t published this year. Given the number of times they were read in 2011, they still made the top-ten list. Just shows the longevity of articles once published here.

1. HDMI/DVI HDCP handshake problems and how to avoid them

“With the advent of affordable 1080p displays, 8-channel 192 kHz sound systems and high-definition A/V sources, consumers are switching to HDMI and DVI uncompressed digital A/V interfaces en masse. Why? Because in many cases these interfaces are the only means to obtain protected content and to maintain pristine quality across long signal chains.  But there's a hitch. HDMI & DVI have a companion high-definition content protection (HDCP) system that sometimes leaves authorized consumers in mute, watching a blank screen, blinking video, or snow while being held hostage by a bug known as the ‘HDCP handshake problem.’

This article, by Mark Stockfisch of Quantum Data, Inc., reviews the key issues surrounding this problem and introduce you to some rules and tools that'll help you keep your HDMI and DVI design out of trouble.”

2. A primer on high-side FET load switches—Part I, Part II

Here’s an in-depth primer on high-side load switches and their operations for applications including battery-powered portable devices such as mobile handsets, mobile GPS equipment, and consumer education gadgets. This two-part series was contributed by Qi Deng from Micrel, Inc.

3. Tutorial on VLANs—Part I, Part II

Part 1 of this article by Manikantan Srinivasan from Net-02 examine the types of VLANs available and the key structures, such as tasks and identifiers, that make VLANs work. Part 2 follows up the discussion by looking at the generic attribute registration protocol (GARP) and GARP VLAN registration protocol. We will also look at emerging VLAN stacking and virtual private LAN service (VPLS) techniques.

4. A tutorial on the Link Layer Discovery Protocol

Nothing like snagging the 3rd 4th and 5th places in the Top Ten. This article, by Manikantan Srinivasan of Net-02 Technologies describes the motivation for LLDP, some sample misconfiguration scenarios, and details the various aspects of LLDP.

5. Designing for Multicast Operation with IGMP: A Tutorial

Another gem by Manikantan Srinivasan, this article takes an in-depth look at the IGMP protocol and its impact in a multicast network design.

6. EPON vs. GPON: A practical comparison

In this article, Onn Haran, CTO at Passavé provides a practical comparison of the two technologies. Key differences between the two technologies and examine the strengths of each protocol, and compares and contrasts usable bandwidth, reach, per-subscriber costs, efficiencies of each standard, management systems, support, encryption, and network protection.

7. Modulation roundup: error rates, noise, and capacity

This article by Krishna Pillai The article compares various digital modulation schemes like BPSK, QPSK, PAM, 16PSK, 32PSK, 16QAM and 64QAM using the following metrics:

(a) Symbol Error Rate vs. Signal to Noise Ratio (SER vs Es/No)

(b) Symbol Error Rate vs. Bit to Noise Ratio (SER vs Eb/No)

(c) Capacity in bits per second per Hertz vs. Bit to Noise Ratio (Capacity vs Eb/No)

(d) Bit Error Rate vs. Bit to Noise Ratio (BER vs Eb/No)

8. Inside the Samsung Galaxy Tab--Taking on the iPad

Our own Allan Yogasingam looked at the design choices Samsung made to ensure its Android-based tablet would be a worthy adversary to the iPad. He looked inside to find out!

9. Home Automation:  Access, automate, and secure with fewer chips

Akshat Gupta from Cypress Semiconductor looked at solutions for home automation that address growing security concerns. The article is divided into four parts:

Sensors: Different sensors and their interfacing with the main controller is covered in this section

Communication between these sensors: This section covers how to send signal over existing power lines and interfacing Bluetooth for wireless connectivity.

User Control and feedback: Control through mobile phones using Mobile Application via Bluetooth, SMS and DTMF tones is covered in this section along with control via Internet. It also covers how the user will know whether device has started working or not once user gives ON/OFF command.

Security measures to prevent intrusion: Security measures for intrusion prevention using existing sensors and surveillance cameras are covered under this section.

10. Charge-Pump Phase-Locked Loop—A tutorial—Part I, Part II

According to author Jeffrey Pattavina, this article describes the fundamental properties of a charge-pump PLL (CP-PLL). The CP-PLL derives its name from the fact that the phase detector (PD) output is a current source as opposed to a voltage source and "pumps" current into and out of the loop-filter. This form of PLL is popular because it is adaptable to integration in microcircuit devices. Therefore we focus the discussion on methods suitable for ASIC design.  We provide mathematical models to study key parameters affecting the loop-bandwidth, peaking, jitter, noise, and transient response.

I'm anxious to see what the list will be for 2012. Please consider contributing and maybe you'll be on the Top Ten list in no time.