Once more you will detect the typical faults marked with XXI and XXII. The bandwidth for the lower GSM bands is very small and the triangle marker 1 for the middle of the GSM 900 band is on the right side of the gap. There is a need for a matching circuit for sure. For […]
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 […]
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 got an update. The mayor news is that everybody who owns a copy of the book will get an export (Touchstone file) out of CST Microwave Studio for import to Atyune. Atyune is a free of charge software to generate a matching circuit automatic. The jitter of the resonate frequency generate […]
Ceramic embedded LTE antenna This LTE antenna with is very detailed documentation is a good example to explain the working of ceramic antennas on a PCB with different size of ground plane. I. Embedded LTE antenna efficiency The antenna is resonating in all major LTE, GSM and HSPA bands and on Wi-Fi 2400 MHz and […]
Selection of ceramic GSM chip antenna I. Size of GSM ceramic chip antenna The size of the ceramic GSM chip antenna is 21 x 7 x 3 mm only. The distance for the selected ceramic chip antenna to the ground plane has to be to be 7 mm. There is a need for a gap […]
April 2014 @ M2M Journal http://www.m2m-alliance.com/fileadmin/user_upload/pdf/m2mJournal/140402_M2M_Journal_low.pdf The example of a locating device based on cellular modules (GSM, HSPA, LTE) and GNSS modules (GPS, Glonass, All Galileo) explains how to develop a complex IoT / M2M-device with embedded antennas. The person, who has to develop a telemetry device, ignores the part of GNSS. The 20 years […]
GSM chip antenna design mistakes in detail I. Size of the ground plane The length of the distance marked with I is 56 mm only. Most GSM chip IFA antennas or PCB track antennas will radiate perfect on an estimated length of the PCB of 90 to 100 mm. Just compare it with the length […]
Q: I am trying to figure out if it is possible to design a reasonable quad band on a PCB that has a total overall size (ground plane plus antenna) of about 60x30mm, using a GSM module. Have you ever tried something around this size? A: Some chapters out of my IoT M2M book: 7 […]
GSM antenna designs mistakes in details I. Size of antenna ground plane If you compare the simulation of the GSM antenna in the IoT M2M Cookbook with the antenna at the picture, then you will understand that the antenna efficiency at GSM 850/900 will be poor, because the PCB is already much to short. Nobody […]