The graph shows the two faults marked with XXI and XXII again. The triangle marker 1 has left and rights a nice gap to cover the 6 dB bandwidth. It is already more than 250 MHz, and to cover GSM 850 plus GSM 900 we need 136 MHz only. Even the gap at GSM […]
Wrong desigend GSM GPS Tracker The two yellow bars on the screen of the vector network analysers mark the – 6 dB return loss target for GSM 900 and GSM 1800. In the lower GSM 900 band the antenna is far away from the -6 dB. The GSM antenna is not an antenna. It is […]
The upper graph shows some interesting details. XXI and XXII are faults generated by the VNA. The peak close to 1100 MHz and 1500 MHz cannot be true. However, the peaks marked with XXI and XXII will be visible in the following graphs as well. Just ignore it and have a closer look on the […]
The four antennas at the picture below promise to be GSM quad band or even GSM quad band plus UMTS 2100. With a low budget VNA we let the cat out of the bag. The antennas have no chance. Our lie detector is called MiniVNA Tiny and will animate the antennas to tell us their […]
By using of a combined FR4 together with Flex PCB is it possible to bend the PCB and to get a good ground plane for the GSM and GPS antenna. Such PCBs can be useful for tracking of animals, banknotes or tracking of security officers.
Latest version of IoT M2M Cookbook IoT M2M Coobook version 2014-10-06 for download IoT M2M Cookbook Table of Contents In September I have written seven more pages. The latest updates of the book are inspired by my consultancy contracts and questions of the readers of the book. In October the book got ten more pages […]
IoT M2M Cookbook – latest news The latest version of the IoT M2M Cookbook made a big jump. I bought a GSM tester and made some measurement reports public. Mesurement report with GSM tester Such a GSM tester emulates a cellular based station. I explain in detail how to use the tester and which reports […]
My IoT M2M Cookbook has now a nearly final version. It explains in details how to move from an idea for a wireless device to a product for mass production. Table of contents: 1 Why to write the IoT / M2M Cookbook? 5 2 Fundamental considerations before starting the IoT / M2M project 5 3 […]
How to develop a device based on wireless modules Table of contents 1 Why to write the IoT / M2M Cookbook? 5 2 Fundamental considerations before starting the IoT / M2M project 5 3 Certifications and approvals 6 3.1 Examples for Radio approvals in EU and US 6 3.2 Examples for Radio approvals in US […]
Presentation about Home Automation on Bluetooth Low Energy – Bluetooth 4.1 The picture shows a proposal for a home automation system on the new specification of Bluetooth 4.1. BT 4.1 describes a hub on Bluetooth Low Energy. A Bluetooth Low Energy device could be a master and slave in same time. Master and slave is […]