Radio-Frequency and Microwave Communication Circuits: Analysis and Design

The products that drive the wireless communication industry, such as cell phones and pagers, employ circuits that operate at radio and microwave frequencies. Following on from a highly successful first edition, the second edition provides readers with a detailed introduction to RF and microwave circuits. Throughout, examples from real-world devices and engineering problems are used to great effect to illustrate circuit concepts.
* Takes a top-down approach, describing circuits in the overall context of communication systems.
* Presents expanded coverage of waveguides and FT mixers.
* Discusses new areas such as oscillators design and digital communication.
*An Instructor's Manual presenting detailed solutions to all the problems in the book is available from the Wiley editorial department.

Thank you for taking an interest in SE International's radiation detection instrumentation.

Since 1979 RADIATION ALERT® instruments have proven ideal for a wide range of applications.

As the manufacturer of our products, we have engineered them to be reliable, simple to use and understand, and affordably priced.

We're dedicated to our customers and promise to help you find the appropriate instrument for your needs.

Emergency Response and Preparedness

Since the event of September 11, we have had an increased amount of calls from individuals wanting to be informed if a radiation event takes place. Radiation is a scary topic for most individuals, but some basic knowledge will help in determining what action to take when exposed to radiation in an emergency response situation.

The types of radiation encountered during such an event are alpha, beta, and gamma. Alpha and beta are particles and gamma is a ray/photon.

A piece of paper can stop alpha and a few millimeters of aluminum foil can stop most betas.

We say most beta energies because there are high energy betas that are more penatrable.

Most people consider alpha and beta not to be of a concern; however, these particles can be ingested or inhaled and cause damage to the body.

There are high and low levels of gamma, but the primary concern with gamma radiation is the amount of time you are exposed to it.

There are two types of monitoring devices that are applicable in an emergency response to radiation.

One is a rate meter/general purpose Geiger counter.

This type of instrument shows the rate that the radiation is being received.

The other is a dosimeter. A dosimeter shows the amount/dose being received.

When measuring radiation in an emergency response situation, it is good to have something to compare your readings to.

Taking a background radiations level in your area before a radiation event, will help you determine if you have a radiation elevation and whether or not to stay in that location.

Background radiation is naturally occurring radiation that is always present.

It includes; high energy gamma rays from the sun and outer space and alpha, beta, gamma radiation emitted from elements in the earth. Using a rate meter, you can determine what your normal background is.

It is up to the individual to decide what a safe radiation level is because it differs depending on the individual and their knowledge of radiation and its affects.

As an example; say your background level is 25 CPM (counts per minute) where you live.

When you fly in an air plane at 30,000 feet your rate meter is getting 200 CPM for anywhere between 2 to 5 hours.

That is 8 times what your normal background is on the ground, but it is for a limited amount of time.

There are non-occupational dose limits set by the government which is 100 mR per year above background per year.

What we suggest for a good emergency response kit for radiation is a general purpose Geiger counter like the Monitor 4, a carbon fiber dosimeter such as the PEN200 and a Charger to reset the dosimeter. T

here are electronic dosimeters, however, if you are in the blast zone of a nuclear bomb the pulse of the bombs render most electronic inoperable but the carbon style dosimeters will still operate.



A Brief Overview of Radiation Detection

None of the instruments listed in this website detect neutron, microwave, RF (radio frequency), laser, infrared, or ultraviolet radiation.

All of the instruments are most accurate for Cesium 137 and isotopes of similar energies.

Some isotopes detected relatively well are Cobalt 60, Technicium 99M, Phosphorous 32, Strontium 90, and many forms of Radium, Plutonium, Uranium, and Thorium.

Some forms of radiation are very difficult or impossible for a Geiger tube to detect.

Tritium is a byproduct of a nuclear reactor and is used in research.

The beta emissions from Tritium are so weak that there are very few instruments that are capable of detecting it.

More sophisticated equipment is needed for the measurement of environmental samples, such as radioactivity in milk, produce, soil, etc., unless you are looking for gross contamination.

The radiation from some isotopes can cause a Geiger tube to overexcite and indicate a higher level of radiation than is actually present.

Americium 241 is an example of this phenomenon.

Americium 241 is used in some smoke detectors and many different types of industrial density and flow meters.

Unless you know exactly what you are measuring and understand the limitations of detection instruments, it is possible to draw misleading conclusions from your readings.

We design our instruments to detect the broadest range of ionizing radiation possible and still be affordable.

The full spectrum of ionizing radiation cannot be measured by one single instrument.

Everyone agrees that radioactive materials can be dangerous. We encourage you to seek out other sources of information.

For undergraduate course in RF electronics and Microwave Circuits and Devices. This highly illustrated resource makes grasping the fundamentals of RF and microwave electronic theory and design easier and faster. Begins at the rudimentary level of axioms and postulates of physical sciences and progresses to introduce low-frequency transistor circuit analysis and design, RF electronics and wave fundamentals, microstrip lines, and the application of the Smith chart in lumped and distributed circuit analysis and design.