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1. Before you start with design in of your embedded antenna you should read these few lines, in order to save time and money. This document is a short summary for design-in on embedded antennas of Aldacom. This technical preparation can never replace the literature on antenna design and specification of RTTE, FCC and PTCRB and maybe further regulations that are related to your product. Think about that, people study many years to be able to design antennas and they have to have years of practical experience to develop good high quality antennas. If you have an education as a chef, then you will not be able to be the head chef in a high-level restaurant. You will start with simple jobs and learn a lot by watching your colleagues. If you have cooperative colleagues then you have a good chance to learn a lot in a short period. We will try to be cooperative colleagues by preparing an enhanced meal. 2. Let us go back to embedded antennas. We have several embedded antennas for you. Each antenna has its benefits and advantages, but maybe limitations as well. Without recommendations and advice, you take the risk to select the wrong antenna for your design.
A short consulting by phone and email we offer free of charge. Finally yet importantly, we can help with customized antennas. After selecting the right antenna, we would like to recommend the following guideline for the antenna. Some simple rules remain equal like: • ·Non-metal components in vicinity of the antenna. What is near differs by the different antenna designs • ·Free space areas around the antenna or sometimes cupper areas as reflectors • ·A ground plane that is big enough. Often antennas are lambda/4 antennas with a need for a ground plane. The ground plane size depends on the lowest frequency you would like to radiate. • ·Micro strip lines with right impedance (most time 50 Ohm) • ·Matching circuit to adjust the impedance, centre frequency or bandwidth of the antenna. Further details are listed in the guidelines of the antennas. A lot of antennas are wired by 50 Ohm micro strip lines. Please feel free to come back to us if you have no tools to calculate the micro strip lines. We also would like to recommend playing with the 3D dimensions of the micros trip lines to get a feeling, which parameters will change if you change distance of the tracks to next layer or thickness of the copper layers or broadness of the tracks. Finally yet importantly, the Epsilon R of your FR4 will influence the impedance of your micro strip line too. Often suppliers of prototype PCBs cannot produce and test PCBs on impedance. They even cannot guarantee the Epsilon R of the PCB. For your first few samples if is OK to calculate with the common average Epsilon R of your PCB material.
3. On your first PCB you should mount the recommended components for matching circuit. In the later period of the development, you can then optimise the matching circuit. For first trial something close to 50 Ohm is fine. At this point it makes sense to use a GSM tester.
A GSM tester simulates a GSM base station. You can select channels beginning, middle and end of the band and force 2 Watt transmit power. Most times the GSM application crashes. What could happen (examples of mistakes and bugs reported): • · Power supply or battery is not able to support the 2 Ampere peaks. By the way, this user mistake is independent on embedded antenna. Power down reset is the frequently done user mistake. In our user forum you will find one message board called “Power supply and power down reset” • · The 2 Watt RF power interfere with the DC power regulator on your PCB and a triggered power down reset • · The 2 Watt RF power interfere with the security electronic in the LIPO battery and generated RF noise on quite other RF bands • · The 2 Watt RF power interfere with electronic components in the PCB and generated RF noise on quite other RF bands • · The 2 Watt RF power interfere with the micro controller on PCB and the micro controller stops to work The offices of our customers are very often in cities or villages. In such locations, most times GSM 1800 or GSM 1900 is in use. Both GSM band support 1 Watt only. The maximum peaks will be 1 Ampere. The base station will be close to you. That means your device has never to support highest power level.
By using of a GSM tester, you have full control and can force the worst-case conditions. Premium customers can loan GSM tester from us free of charge.
4. If the PCB with antenna design-in and all other components in a final stage you should start with developing the matching circuit. Final stage means final PCB and final enclosure. Think about that the plastic box will impact on the parameters of the antenna, too. For this task, you will need a network analyzer and some experience how to work with such a tool.
If you have no capacities for this task, we can offer this as a service as well. If your PCB will not fit to our design rules, we will charge a handling fee without making further optimization and give the prototype back to you. We recommend hiring a freelancer if you have concerns or problems by design-in off embedded antennas.
Let us look forward. Your PCB has no problems in the upper mentioned mistakes and bugs. The PCB has a final stage and the plastic enclosure is ready with final plastic. In this stage of development, you will forward your final product to us.
We will have a look at the design and maybe replace the antenna you got to another in same shape. If we see that the matching circuit is not perfect, then we will come back to you with an offer for optimization. Please take care that the PCB you forward to us has impedance tested micro strip lines. If you change the PCB later, then all effort for optimization is lost. The easiest and cheapest way for us is to ensure that the antenna can stay as it is and matching circuit is perfect. It may be that we have to replace antenna and matching circuit on the PCB with enclosure that you have given to us.
5. If you plan to retail your product in the United States, you need - in worst case - a budget of USD 25.000 for a customized antenna design. You also will need a budget of USD 50.000 for the PTCRB approval. Cingular, the biggest GSM operator in the States asks for an approval for any product based on an approved GSM module again. They will ask for an efficiency of the antenna of at least 50 % on the whole GSM band.
Integrated devices must complete PTCRB testing by an approved test laboratory. The exact amount of testing and cost is determined by an approved PTCRB test laboratory. Typical testing can include the following areas: • · Audio interface • · Power interface • · SIM interface • · RF interface • · MMI interface • · Other testing including TRP/TIS Radiated Performance
PTCRB testing of an integrated device with a quad band module typically costs between $30,000 - $60,000 USD. Contact approved PTCRB test labs for exact testing prices for your integrated device
. In order to start PTCRB testing you will need to open a project with CTIA (http://cpo.ctia.org). The cost to open a project for an integrated device is $3,250 USD. Full details of the PTCRB process for integrated devices are described in the NAPRD0 document. It is recommended to use the same test house for both FCC and PTCRB testing. This can save money since this will ensure certain testing is not completed twice. (http://cpo.ctia.org). The cost to open a project for an integrated device is $3,250 USD. Full details of the PTCRB process for integrated devices are described in the NAPRD0 document.
6. Certification requirements for Cingular, KORE Wireless, & Aeris Cingular, KORE Wireless, and Aeris have the following requirements before accepting an integrated device for testing: • GSM module inside integrated device must have FCC, PTCRB, and Cingular approval • Integrated device must have PTCRB approval (using same module software version approved by Cingular) • Integrated device must have FCC approval
Additional Details on Cingular process for integrated devices If your integrated device will be used on the Cingular, KORE Wireless, or Aeris GSM networks it will need to complete Cingular acceptance process for an integrated device. This process is free but takes time to complete. Please see the attached documents and the Cingular developer’s web page (http://developer.cingular.com) for full details. You will need to register on the Cingular developer’s site for full details on integrated device certification. Certification requirements for Jasper Systems Jasper Systems has the following requirements before accepting an integrated device for testing. • GSM module inside integrated device must have FCC and PTCRB approval • Integrated device must have PTCRB approval (using a PTCRB approved module software version) • Integrated device have FCC approval
Certification requirements for T-Mobile (Preliminary) • T-Mobile has the following requirements before accepting an integrated device for testing. • GSM module inside Integrated Device must have FCC and PTCRB approval • Integrated device must have PTCRB approval (using a PTCRB approved module software version) • Integrated device have FCC approval Example Certification Plan and Example Budget Example Integrator Certification Plan This section will provide a high level integrator certification plan for entry into the US market. This plan does not associate timing with each step Integrated Device Certification Plan I. Select GSM operator to use II. ·Test product in US markets with GSM module with the correct approved software version III. ·Perform pre-certification lab testing IV. ·Contact approved test house for quotes on PTCRB and FCC testing V. ·Select test house - http://www.ctia.org/certification/test_labs/index.cfm VI. ·Open project with CTIA for PTCRB approval - http://cpo.ctia.org VII. ·Submit product samples and proper documentation to test house and CTIA for testing VIII. ·Complete PTCRB and FCC testing and receive approvals IX. ·Present business case to operator (This step can be completed earlier in this process) X. ·Get scheduled in the operator lab for testing XI. ·Receive operator approval XII. ·Sell product in the US Example Budget for certification costs This section will provide a high-level budget for certification costs for entry into the US market • $25,000 USD – Pre-certification lab testing • $10,000 USD – Pre-certification lab testing • $10,000 USD – Field testing in the US market • $3,250 USD – Opening a project with CTIA (for PTCRB) • $30,000 USD– PTCRB & FCC testing TOTAL = approx. $78,250 USD We recommend starting in Europe, Australia, Asia or South America, for the beginning. Please be so kind and ask us, why it is so expensive and why there are so many efforts needed. Further details you get by signing a consultancy contract with one of the laboratories.
7. Acronyms and Abbreviations • ·CTIA - Cellular Telecommunications Industry Association • ·FCC - USA Federal Communications Commission • ·IC - Industry Canada (the FCC of Canada) • ·PTCRB - PCS Type Certification Review Board • ·NARPD - PTCRB Test Requirements Document
Links • PTCRB – www.ptcrb.org • CTIA – www.ctia.org • FCC – www.fcc.gov |