Design Articles

 How to Simplify the Design of an RF Remote Control
Remote controls come in many different sizes, shapes and wireless technologies and are widely used in the consumer market as accessories for a wide range of products, such as televisions, video games, stereo systems, lighting controls and home automation including garage door/gate openers, air conditioning units, fans and automobiles with remote keyless entry (RKE) key fobs. Read

RF Receiver Front-End Topologies for Software Radios
A number of different RF front-end topologies are appropriate for software radios, each with its own advantages and disadvantages. This article explores the tradeoffs involved with each approach. Read

Challenges with Measuring Current when Developing of Power Management Schemes for Battery-Powered Devices (Part 2)
In order to optimize power consumption and maximize battery life, engineers typically utilize advanced power-management schemes that rapidly turn on/off sub-circuits as necessary, creating dynamic current consumption typically from uA to A. Unfortunately, traditional test instruments are not well suited for this type of measurement requirement. Read

Ultra Low Power 802.11n Wi-Fi – Wireless Connectivity for “The Internet of Things”
The IEEE 802.11n standard was proposed through a ‘High Throughput Study Group’ effort at the IEEE.  Although the major focus of the standard has been on deriving high user throughputs in a WLAN environment using multi-stream MIMO techniques, the standard’s benefits are not limited to devices with multiple antennas.  There are a plethora of devices that require ultra-low power connectivity. Computers, electronic devices and machines all talk to each other exchanging volumes of information in a variety of scenarios. More than just communicate with each other, these devices form a vast, IP-based network – ‘the Internet of Things.’ In this article, we look at how these low power battery operated devices can benefit from 11n and why new designs will use 11n rather than 11g. Read

Challenges with Measuring Current when Developing of Power Management Schemes for Battery-Powered Devices (Part 1)
 In order to understand if a design has achieved an improvement in runtime, an engineer needs to be able to measure current being consumed by the device and determine if his optimized design has indeed lowered overall current consumption.  In this article, we will cover methods used to measure current flowing from the battery into the electronic device (or within sub-circuits of the device) and how modern power management schemes create challenges for measuring these currents. Read

Designing RF Mixed Technology Boards
For most of the century-plus that RF circuits have been designed and built, RF has been treated as a highly specialized task, and as such has been more-or-less been isolated, both in design and on the printed circuit board (PCB). With the advent of the handheld cell phone, there was no longer the luxury of having an isolated PCB just for the radio components. Read

 Frequency Hopping Diversity Improves Low-Power Wireless System Performance
The motivation for the article is to present methods of enhancing a wireless link in a typical environment of simple low-power wireless transceivers. This article focuses on maximizing the reliability of a wireless link, while keeping the overall hardware costs down. Read

 Joint Tactical Radio System: AMF, GMR, HMS
The JPEO JTRS team at SPAWAR San Diego and PEOC3T Fort Monmouth, NJ is leading the development and testing of the Airborne Maritime Fixed (AMF), Ground Mobile Radio (GMR) and Handheld, Manpack and Small Form Factor (HMS) radios. These radios will be capable of communicating in the Global Information Grid using 9 waveforms and 13 radio form factors, including 7 small form factors (SFF). Read

Key Priorities for Sub-GHz Wireless Deployment
Wi-Fi, Bluetooth and ZigBee technologies are heavily marketed 2.4 GHz protocols used extensively in today’s markets. However, for low-data-rate applications, such as home security/automation and smart metering, sub-GHz wireless systems offer several advantages, including longer range, reduced power consumption and lower deployment and operating costs. Read

Simplifying Android Migration
 Android is not just an operating system (OS), but a complete handset platform, combining a mobile OS kernel, a Java run-time (Dalvik), a telephony interface, and other middleware, plus browser and application environment. Integration of such a comprehensive package in a handset design would appear to demand an all-or-nothing approach. As tempting as developers might find a blank slate, existing investments, innovations, and expertise built on current platforms cannot realistically be abandoned in favor of an all-encompassing new technology. Read

CMOS Power Amplifier Technology
Traditionally, the power amplifier (PA) has been the last bastion of non-CMOS technology. Typically, this block is manufactured using a specialty GaAs or LDMOS process coupled with a hybrid module packaging technology, in total an expensive manufacturing flow, which has made it a substantial part of the cell phone bill of materials. The specialty semiconductor process is required to provide a high gain, high frequency transistor element with a high breakdown voltage. The hybrid packaging technology provides high Q passive components to generate the 50 Ohm matching circuit. Read

Putting Intelligence in ‘Bricks’
The size and weight of early public safety portable radios led them to often be referred to as “bricks”; while that reference had more to do with the physical characteristics of a radio, it also implied that the radios were not all that sophisticated. Today’s public safety radios, however, incorporate a significant amount of software that processes RF signals. In fact, most high-end portables fit typical engineering definitions of software defined radios. Read