patternCustom

Plot radiation pattern using spherical coordinate system (phi and theta angles)

Syntax

patternCustom(magE,theta,phi)

patternCustom(magE,theta,phi,Name,Value)

hplot = patternCustom(___)

Description

patternCustom(magE,theta,phi) plots the 3-D radiation pattern of an antenna magnitude, magE over the specified phi and theta angle vectors.

hplot = patternCustom(___) returns handles of the lines or surface in the figure window. This syntax accepts any combination of arguments from the previous syntaxes

Examples

Visualize Radiation Pattern From Antenna Data File

Consider a helix antenna data file in .csv format. This file contains the magnitude of the antenna directivity in phi and theta angles. Read The File

Command : openExample('antenna/VisualizeRadiationPatternFromAntennaDataFileExample')

helixdata = csvread('antennadata_test.csv',1,0);

Use patternCustom to extract the magnitude of directivity, and the phi, and theta angle values. Plot the 3-D polar radiation pattern.

patternCustom(helixdata(:,3),helixdata(:,2),helixdata(:,1));

Visualize Radiation Pattern From Antenna Data File

Use the same data to plot the 3-D rectangular radiation pattern.

figure

patternCustom(helixdata(:,3),helixdata(:,2),helixdata(:,1),...

'CoordinateSystem','rectangular');

3D Rectangular radiation Pattern

Visualize 2-D Radiation Patterns of Helix Directivity

Calculate the magnitude, azimuth, and elevation angles of a helix's directivity at 2 GHz.

Command :

openExample('antenna/VisualizeRectangularAndPolar2DRadiationPatternOfHelixExample')

h = helix;
[D,az,el] = pattern(h,2e9);

Here, az = the angle from the positive x-axis to the directivity vector's orthogonal projection onto the xy plane, moving in the direction towards the y-axis.

el = the angle from the directivity vector's orthogonal projection onto the xy plane to the vector, moving in the direction towards the z-axis.

Extract theta and phi angles of the directivity magnitude.

phi = az';
theta = (90-el);
MagE = D';

Plot 2-D phi slice of the antenna in rectangular coordinates.

figure;
patternCustom(MagE,theta,phi,'CoordinateSystem','rectangular',...
'Slice','phi','SliceValue',0);

Plot 2-D phi slice of the antenna in rectangular coordinates.

Plot 2-D phi slice of the antenna in polar coordinates.

figure;

patternCustom(MagE, theta, phi,'CoordinateSystem','polar',...

'Slice','phi','SliceValue',0);

Plot 2-D phi slice of the antenna in polar coordinates.

rf bnc 50 ohm attenuator

Attenuators - Interconnects PADS BNC 50 OHM BNC(M) (F) 20db -

Is 20db enough attenuation to reduce 1W output to 0.5W ?

20dB for this attenuator provides drop of voltage 10 times into 50 Ohms load. The power which is V^2/R will drop 100 times accordingly . The difference between 1 watt and 0.5 watts is 3 db. A 20 db attenuation is 1/100. 1 watt input gives 0.01 watt output. It will reduce your 1 Watt to .01 Watt. If you really need 0.5 Watt , then you need a 3 DB attenuator. It goes loke this: 3 db = half the power; 6 db = one fourth the power; 9 db = one eighth of the power; 10 db = one tenth of the power; 20 db = one one-hundreth of the power. Said another way: for every 3 db of attenuation reduce the power by one-half. For every 10 db reduce the power by a factor of ten A 3db drop is half power.

What's the working frequency range of this attenuator? I need one working between 0.5 and 3 MHz with minimal distortion of the waveform.

I use them on 490MHz all the way to 875MHz, don't see distortion on waveform but I mainly use them to drop the signal so I don't overload enritsu or pathtrax.

What is the maximum power input in Watts for this attenuator?

Max power input isn't indicated on the attenuator itself, but I've been running 1/2W through it without any problems so far.

will this attenuator work @ 30mhz and below ? I want to attenuate the input on a spectrum analyzer for use on the HF bands

You are looking at a resistive Attenuator. Should work all the way down to DC as long as you keep the power level low. At the upper frequency range you are limited by the BNC connection but should be good to 1GHZ.

Find The Best Guide to Indoor and Outdoor TV Antennas

Indoor Antennas for receiving DTV

(Note: An auction of spectrum that had been licensed to broadcast television stations operating on UHF TV Channels 38-51 resulted in many TV stations on these channels transitioning to other channels. Almost all of the TV stations affected finished transitioning in July 2020.)

To receive DTV signals from all stations in the area, your antenna needs to be able to receive both VHF channels (channels 2-13) and UHF channels (channels 14-36).

Some antennas only provide good reception of VHF or UHF channels, but not both. For example, indoor "rabbit ears" usually need to be augmented with an additional "wire loop" or "bowtie" antenna (see images on the next page) in order to pick up signals on UHF channels.

Many of the antennas being sold as "HDTV Antennas" perform best at receiving UHF signals, but perform less well receiving VHF channels. Check with retail consultants and consumer websites to make sure that any antenna you choose provides good reception of both VHF and UHF channels.

Even if you use a digital-to-analog converter box, you will still need to use an antenna to receive DTV signals. Digital-to-analog converter boxes do not contain additional antennas or signal amplification.

Antennas for reception in different signal conditions

The antennas on the next page will work for the indicated signal strength in most instances, but may not work in all cases.

The type of antenna needed at a specific location may vary depending on geographic location, the height at which the antenna is used and other local factors such as nearby buildings, trees, terrain or home construction.

Generally, outdoor antennas will get better reception than indoor antennas and are strongly recommended for the most reliable reception.

If your home near the TV Broadcasting Station and not much blocking obstacles such high building and the TV signals is Strong Use Circular Loop and Dipole Antenna such Rabbit Ears Antenna.

Jump to my recommendations for Indoor Antenna!

Best Practical Antenna HandBook by joseph J. Carr for Hobbyist, Students, and DIYers

Are you looking for practical antenna book ?
tired reading theory from other books and literature
are you looking for antenna books that can implemented for your business , companies, and hobbyist ?
Now you can get the practical antenna books in here

from the practical electronics engineer/antennA Hobbyist that have more 35 years experienced in antenna field/ master and guru in antenna field

joseph j. carr

BEST HANDBOOK FOR UNDERSTANDING PRACTICAL ANTENNA - ORDER IT NOW

Practical Antenna HandBook 5/e 5th Edition - This Book is a practical antenna handbook ,by Joseph J. Carr , a book that explains antennas in terms of theory and practical examples to apply, suitable for Hobbyist, Students, and DIYers. Practical Antenna Handbook is a thick volume that tries - mostly successfully - to balance technical detail against practicality.

The most popular book on antennas ever written and unquestionably the world's favorite antenna book, Joseph J. Carr's Practical Antenna Handbook, fourth Edition and Fifth Edition.

Joseph J. Carr

Is was a military electronics technician and the author of several popular electronics books, including McGraw-Hill’s Secrets of RF Design, Third Edition and Old Time Radios! Restoration and Repair. He wrote a monthly column for Nuts & Volts magazine.

George W. (Bud) Hippisley,

Is W2RU, earned his BSEE degree from MIT, and was formerly chief operating officer for a major supplier of electronics to the cable TV industry. A long-time active amateur radio operator who has won or ranked nationally in many competitive on-the-air operating events, he has given talks on the basics of antennas and ionospheric propagation to radio clubs and other groups for more than 35 years.

Several article from Practical Antenna Handbook you can find in this blog, and this This intended to let the reader knows the contents of this book, this book combines theory and practice very well and clearly, suitable for hobbyists, scientists, college students, or anyone interested in antenna

In this book you will learn about Introduction to radio communication, radio wave propagation, Antenna Basics , dipole antenna, standing waves antenna, transmission lines, impedance matching, Antenna Arrays, Antenna Gains, High frequency Antennas, Wire Loop Antennas, Multiband Antenna , Tune able Antenna, Wire Antenna, Yagi Uda Antenna, Microwave Antenna, Mobile Antenna, Marine Antenna, VHF Antenna, UHF Antenna, Smith Chart, Antenna Software , Tower Antenna and etc.

The ARRL Antenna Book for Radio Communications

The ARRL Antenna Book for Radio Communications has everything you need to design your own complete antenna system. Since 1939, it has maintained its place at the forefront of Amateur Radio technology a single resource covering antenna theory, design and construction, and practical treatments and projects. In this edition, The ARRL Antenna Book describes hundreds of antenna designs: wire, vertical, portable and mobile, and new high-performance VHF/UHF Yagi designs.

Radio amateurs continue to make contributions to the state of the art in antenna design and construction. The available tools have grown in sophistication by leaps

and bounds over the past years. Antenna modeling with the low-cost or free programs available to amateurs has completely changed antenna design and development.

A large set of antenna models designed for use with EZNEC 6.0 demo software is included.

Updated to reflect the latest advances and technologies, this 23rd edition is full of antenna designs pioneered by dozens of radio amateurs:

New Projects: Multiband HF antennas from 160 through 10 meters, A simple omnidirectional satellite antenna system, More popular Moxon antenna projects on CD-ROM,

Stealthy and portable antenna designs for home and away.

The ARRL Handbook for Radio Communications 2019

Radio Experimentation, Discovery, and Achievement. The ARRL Handbook for Radio Communications is a complete reference and guide to radio technology principles and practices. Since 1926, The ARRL Handbook has been a trustworthy source of introductory, applied, and theoretical information.

Now in its 96th edition The Handbook continues to advance the pursuit of experimentation and innovation by radio amateurs and professionals. Each edition contains new and useful material to support Amateur Radio activity from the traditional short- and long-wave frequencies through microwaves! Key Topics Radio electronics theory and principles Circuit design and equipment Radio signal transmission and propagation Digital and analog modulation and protocols Antennas and transmission lines Construction practices.

Who reads The Handbook? Amateur Radio operators, or hams; professional wireless communication engineers and system designers; electrical engineers; students and instructors of engineering, physics, and geoscience.

Always Updated! New Projects and Content Simple SLA Float Charger project by John Boal, K9JEB Amateur Radio Data Platforms by Paul Verhage, KD4STH and Bill Brown, WB8ELK The latest information on WSJT-X digital modes by the WSJT team Filter and circuit design software by Tonne Software and Jim Tonne, W4ENE Low-Noise VHF and UHF Oscillators by Ulrich Rohde, N1UL, and Ajay Poddar, AC2KG Update on Solar Cycle 24 by Carl Luetzelschwab, K9LA Updated SSTV practices and technology by Larry Peterson, WA9TT.

Designing dual-band loaded dipoles by David Birnbaum, K2LYV Latest transceiver survey by Joel Hallas, W1ZR Plus, new component tables, reference articles, material characteristics, and guidelines for SDR design. Download Included: eBook and Supplemental Material Download the fully searchable digital edition of the printed book, as well as expanded supplemental content, software, PC board templates, and other support files.

Epic Daily Deals

1. Antennas Direct ClearStream 2V TV Antenna

Deal Price $78.33

~~Normal Price $119.99~~

Multidirectional Antenna, for Indoor, Attic and Outdoor use, VHF/UHF Band, 60 miles range

2. Amplified Indoor HD TV Antenna

Deal Price $18.69

~~Normal Price $24.99~~

Built in high quality nano antenna, Indoor use, with Amplifier signal booster included

3. Tv Antenna Indoor

Deal Price $23.99

Save $5 when apply with coupon

4. Digital Outdoor Amplified hd tv Antenna

Deal Price $46.99

~~Normal Price $99.99~~

Get this Outdoor antenna, with anti storm, anti sun, anti snow, anti wind protection, with J pole mounting, and support 2 TVs at the same time without no splitter.

5. Amplified HD Digital TV Antenna

Deal Price $29.98

Save an extra 5% when apply with coupon

Elegant Antenna design, with amplifier signal booster

6. Mohu Leaf Plus Amplified Indoor TV Antenna

Deal Price $54.99

~~Normal Price $59.99~~

This antenna design to blend with your home decor, hang on your wall or your window for the best performance

7. Five Star Outdoor HDTV Antenna

Deal Price $89.95

Save an extra 8% when apply with coupon

With 4 way splitter or 4 TVs connected in the same time, Water Resistant, windproof, Intelligent high gain, UV Resistant, with 4G LTE filter and FM/VHF/UHF Band

8. Digital Intelligent 2-in-1 Indoor Tv Antenna