19 Replies Latest reply: Jul 6, 2014 10:59 AM by Harald Naumann RSS

Why paying for an embedded GSM antenna if you can get the antenna for free?

Harald Naumann Expert
http://www.gsm-modem.de/M2M/wp-content/uploads/2011/02/ifa-antenna-gsm-umts.jpg

The antenna at the picture or a lot of other embedded GSM antennas  you will get free of charge. There is no reason to pay for. You just  have to spend an area of estimated 800 to 1000 mm² on your PCB. You do  not like the published antenna shape and you are looking for an other  type of embedded GSM UMTS antenna? Then do not hesitate to ask for your  customised version.

 

In the magic world of embedded GSM  antennas everything is cycling around the wavelength named Lambda or  better said the quarter of the wavelength = Lambda/4 .

 

The red coloured part of the picture  view is the part of antenna that will radiate at the lower band GSM 850/  900MHz. A+B+C+D = 79 mm.

 

The green coloured part of the draft is the area that will radiate at the higher bands like GSM 1800/1900.  I +F = 41 mm.

The yellow part of the picture is showing  the feeding line and the three rectangle black  blocks are maybe  capacitors or coils for the matching circuit.

The blue, red, green and yellow coloured aeras are cupper on FR4 PCB.

 

The gap between the branches of the  antennas to the blue area is related to the bandwidth of the embedded GSM  antenna. The blue part is called ground plane and has to have a size of  3500 mm2 to 4000 mm2. If it is less, then the efficiency of the  antenna will be less as well. All lambda/4 GSM antennas has to follow  this rules. Test it yourself and compare the size of your phone with the size  of the mobile phone of your friend or an 5 years old phone.

 

Do you have further questions and would like to start the development of an own wireless M2M device right now?  We  will be glad to share our more than 15 years in GSM and GPS plus 25 years in radio communication with    you. Just send an e-mail to harald.naumann (at) gsm-modem.de .

  • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
    Luciano Cesar Alakija Palma Newbie

    It seems to be very easy if you are not worried about all the drawbacks that a bad antenna design can generate.

     

    For example, when you are dealing with portable devices (like POS terminals - it's part of the M2M market) there are some other effects happening, like absorption and detuning of the antenna due to handling.

     

    Also, following the phisycal principles you mentioned, the antenna volume has an impact on the bandwidth. So, if you do your own PCB trace antenna and it's all correct, it will have to be larger than an off-the-shelf antenna. Considering that many M2M devices are also following the miniaturization trend, the trade-off between the antenna size and eficiency required on desired bands is not an easy task to solve. In many cases, eyes are only on the size, not on the real function of the antenna that it's to radiate.

     

    Moreover, some customers do not consider that THE POSITION of the antenna has a big impact on the overall performance and on embedded antennas, there is an issue called interference that already caused many headaches on certification process. In general, you will prefer to have more confidence that there is no problem on certification and also in the field due to a poor antenna design.

     

    Additional to that, any antenna is influenced by it's sourrounding, so it's necessary to test the performance on the product, considering it's constraints. And to do a conclusive test, it's necessary to have some high cost infrastructure (like anechoic chamber or satimo stargate, base station simulator...) that should not be the focus on the product company.

     

    And carriers do not like to have poor antenna designe devices hanging on it's network and taking capacity and affecting the percepion of coverage. This is why CTIA has it's Certification Test Plans establishing minimun TRP and TIS requirements for devices checking over the air performance.(http://www.ctia.org/business_resources/certification/index.cfm/AID/11259).

     

    Finally, there are more devices with multiple bands like cellphones today incorporating GPS, WIFI, 8 cellular bands, bluetooth, etc... rx diversity,... More and more, the isolation of the antenna and it's surrounding is becoming critical on smaller devices.

     

    All of this may give a credit to an antenna specialist. By the way, it's interesting that some designs are patented, so just copy a design may lead to IP issues.

     

    There is only 1 Steve Jobs in the world who can transform a real antenna issue in a impressive turnaround of sales decline. (even Apple still had to provide how treat antenna serious: http://www.apple.com/antenna/

    • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
      Harald Naumann Expert

      Steve Jobs and me were not at same University. Maybe Steve just forget to contact me.

       

      > So, if you do your own PCB trace antenna and it's all correct, it will have to be larger than an off-the-shelf antenna

      Or maybe it is already smaller. With a IFA or PIFA you can reach a smaller shape then PCB antenna and its coaxial cable. Antennas with coaxial cables does need a distance to ground plane. IFA or PIFA does need 5 mm to 8 mm only.
      It will be often smaller, but it will be cheaper for sure. Try to match USD 0.

       

      > By the way, it's interesting that some designs are patented, so just copy a design may lead to IP issues.
      Only, if you use a patened design and only if the patent is registered in your country. 
      Additional to that, any antenna is influenced by it's sourrounding, so  it's necessary to test the performance on the product, considering it's  constraints

      And an out of the shelf antennna has to be tested on performance too. By a selfmade antenna you can optimise the bandwidth by changing the distance between ground plane and branches. You can play with the lenght of the branches and can optimise it yourself. By an out of the shelf antenna you can not change anything.

      Moreover, some customers do not consider that THE POSITION of the antenna has a big impact on the overall performance

      You are right. And that is the reason, why customers of mine often pass the tests more often than others. Myself is creating around the antenna shapes. The BIGGEST enemy of mine if often the designer of the plastic enclosure. They often would like to have round shapes and I love it rectangle. If money does not matter, then they can use any shape they like. Any shape means any amount for the antenna design as well.

      • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
        Newbie

        Hi Harald, firstly please stop using pictures of our antennas (your picture is a Taoglas PC.28) in your blogs advertising a service that you can not actually provide. You are misleading people, just trying to generate leads to sell other components. Multiband trace antennas are complex and take a lot of time. We have real examples and normally trace antennas are plan B or plan C if plan A is not gettting device certification. If this worked we could fire our engineers, sell the chambers and all the equipment and have kindergarden antenna design competitions. Not being an antenna engineer myself I would be delighted to do that. However, I think the best hope for the drawing is with McDonalds as a happy meal toy.

        • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
          Harald Naumann Expert

          However, I think the best hope for the drawing is with McDonalds as a happy meal toy.

          Dermot, can you believe that we have antenna designers in Germany, UK, Italy, France, Spain and all other countries too? You wil find such people all over the world.
          Anyhow, the antenna design at the picture is already in use and is not that complex. Non antenna engineer will be able to simulate the antenna by using of software like CST. Often the student version is enough. Some skills in electronic will be helpful. As long you use rectangle antenna structures and to not try to reach the smallest design, you have a good change to reach the goal. To compare with a Hamburger is maybe wrong. It is better to compare with a sandwich.

           

          The simulation is a sandwich of:

          • Plastic with Epsilon R of X and thickness of Y
          • Air with Epsilon R of 1 and thickness of Y
          • Cupper structure on FR4 and thickness of Y
          • PCB with Epsilon R of 4,3 and thickness of Y
          • Cupper structure on FR4  and thickness of Y
          • Air with Epsilon R of 1 and thickness of Y
          • Plastic with Epsilon R of X and thickness of Y

           

          Not only you have plan A, B and C. Other people has it too.They have real examples. I will keep you posted.

           

          You shall compare apples with apples. An out of the shelf antenna or an customised antenna will not protect any user of it against interference with other componets on the PCB. The only what will help against that will be not to play with GSM modules or antennas and to use carrier pigeons. If that will happen, then I will start in carrier pigeons business and you maybe will sell your chamber.

           

          You shall not fire your engineers, because there is still a need for special more complex antennas structures like in the picture as below. The GSM antenna could be one of yours. The GPS antenna could be one of your as well. If there is enough space left, then the GPS antenna could be a PCB track only. State of the art GPS modules like comes with

          • Miniature size of 9.6 x 9.6 x 1.85 mm
          • Ultra high sensitivity:
          • - 147dBm (cold start)
          • - 163dBm (tracking)
          • Low Power Consumption: 56mW@1.8V
          • 500uA average power consumtion with SiRF Aware
          • and self assisted A-GPS

          The LNA and the SAW filter is already a part of the GPS module. Sorry, but that is the trues. There is no need for active GPS antennas anymore.

          http://www.gsm-modem.de/M2M/wp-content/uploads/2010/12/flex-pcb-bend-GSM-GPS1.jpg

           

          http://www.gsm-modem.de/M2M/wp-content/uploads/2010/12/flex-pcb-bend-GPS-GSM.jpg

        • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
          Harald Naumann Expert

          Embedded antenna design examples

           

          PCB antenna GSM UMTS HSPA 300x256 How a good embedded antenna design will look like? EA#

           

          • PCB antenna dualband – inferted F antenna
          • Type: Inferted F antenna
          • Multiband (e.g. GSM 900 / 1800 or GSM 850 / 1900)
          • Easy to tune on center frequency
          • Easy to tune on antenna impedance
          • Size of antenna structure: 50mm x 10 mm
          • Size of ground plane: 50 mm x 90 mm
          • Size of hole PCB: 50 mm x 100 mm

          This M2M device was designed by following all important rules for embedded antenna design. The developer got advice by an engineener with skills in antennas and long time expierence in development of M2M devices. In this M2M design, the embedded PCB antenna was selected first. The ground plane lenght was selected by the lowest to frequency to transive. If you have a closer look, then you will see that there is no holes for screws in the corners of the device. The ***** is very close to the radiator for GSM 850 / 950 will be made in plastic. This will help to minimise the parasitc load to the antenna. Between the GSM module and the embedded PCB antenna is a semicondutor that works as a 50 Ohm switch to an external antenna. The first quick performance test with the embedded channel scanner of the GSM module. The scanning with external magnetic mount GSM antenna on big metal plate to get best ground plane parallel to the embedded PCB antennas has shown, that the embedded GSM antenna catch more GSM base stations then magnetic mount antennas. The M2M device is in use in inside vending mashines. Even inside the signal strenght is high enough to save the USD 4 for the external magnetic mount antenna, the drilling of holes at vending mashines and the manual work for mounting antenna and coaxial cables. This saves further USD 8. All together the solution saves USD 12. The size of the first project is 4000 vending machines. This project customer will save USD 12 x 4000 = USD 48.000 with the first vending project.
          Do not hesitate to drop an email to harald.naumann (at) gsm-modem.de to get advice on how to design a M2M device. On request you can get the contact details of this project customer as well.

      • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
        Luciano Cesar Alakija Palma Newbie

        Dear Harald,

         

        Steve Jobs and me were not at same University. Maybe Steve just forget to contact me.

         

        Actually Steve Jobs dropped from Reed College after 6 months to attend classes that were really interesting to him. And his 3 simple histories may give you an idea that he may have other big issues in mind

         

         

        it would be good to see on this video that great ideas when copied (like the font types) become comic - if not a shame - for those who see from outside... For antennas, I invite you to meet Ethertronics patented IMD design (http://www.ethertronics.com/technology/technology_overview/)... it's better in terms of isolation, size and efficiency than conventional PIFA designs.

        If you really would like to understand better our competitive advantage, see this: http://www.ethertronics.com/file_library/File/Advances%20in%20High%20Performance%20Ceramic%20Antennas.pdf

         

        And if you become interested you may see a list of some small and high isolated antennas (Cellular, GPS, WiFi, BT, ... ), try:  http://www.ethertronics.com/products/

         

        Maybe if you just test the difference between one of our antennas integrated on your product and the ones you have been aware of, you will understand the difference.

         

        In the case of Apple, even having infrastructure and investment showing how serious they are with antenna (http://www.apple.com/antenna/), the innovation to position the antenna on the external part of the Iphone4 required more expertise... I am sure that if Steve had a clue about the importance of the antenna and the bad effect on Apple brand it caused, he would have opened up to talk with experts on the issue (as it was made after...), and this would not be you, sorry.  In my opinion, the problem was (and still is) this reasoning you are spreading around by consider antenna as a "simple free commodity thing" and less important than battery for example, rather than the most important structure of a wireless device. Well, considering the antenna as the most important subsystem of a wireless device it is a counter sense that you will get it "for free" from those who know how to make it really work well under all unfavorable conditions. At least those who value antenna and RF knowledge will also be clever to not provide it for free.

         

        Coming back to your expertise on antenna,

         

        And an out of the shelf antennna has to be tested on performance too. By a selfmade antenna you can optimise the bandwidth by changing the distance between ground plane and branches. You can play with the lenght of the branches and can optimise it yourself. By an out of the shelf antenna you can not change anything.

         

        All antennas need to have it's performance tested. Off the shelf antennas also need to be tuned, so you also play around with matching circuits, ground plane clearance and ground length. So you can, actually, change "manythings" on an out-the-shelf antenna. Again, another public example from Ethertronics is the multiband antenna techniques applied for FM and mobile TV (http://www.nabfastroad.org/EmbeddedFM_TVAntennaFinal.pdf).

        Actually we already have results for a single active multiband antenna applied for different technologies (from cellular to WiFi ...) and also have our technology used for Rx diversity and MIMO applications. it will be ijnteresting to see how you can address this situation of two or more antennas close to each other... You will understand why there are experts on the issue.

         

        Out-of -the shelf x pcb trace

        The difference is that the integration of the pre-designed antenna is in general faster than an new antenna once you follow some basic guidelines. So integrating an of the shelf antenna does not need RF experience and I am sure this is a very good option for those who do not want to jeopardize a new project. If you follow application notes guidelines you will certainly have high performance operating. On the other hand if you try to design by your own, it may take longer to fit and get a high performance device. It's also possible, but you need tools, experience and infrastructure to do customized projects. We also do pcb traces but we license our design, and customers are very happy to pay for the excellence.

         

        Finally, thanks for this opportunity to clarify some issues regarding antenna. Hope that you and other players in the industry stop putting different antenna designs on the same box and also wake from this dream world where knowledge and expertise become a commodity offered for free.

         

        Regards,

        Luciano Alakija

        • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
          Harald Naumann Expert

          Dear Luciano, I am aware Ethertronics antennas. One of my customers asks me for an antenna design, that they can use free of charge. What I shell answer? Sorry, I have no antenna design for you? This will not be the true and will not be fair as well.

          Shell I mislead them and tell, that there is no free of charge design?

          It is a simple mobile data logger with GSM and 2400 MHz link. I am supporting the GSM part only right now. The 2400 MHz part is supported by one of my competitors. They support the customer with a 2400 MHz RF chip and an 2400 MHz antenna design on PCB. The 2400 MHz antenna design is licence free as well.

          There no money for embedded chip antennas for GSM and 2400 MHz left. Everything has do be the cheapest of the cheap. The PCB will be a 4 layer PCB of FR4. The micro controller will be a low power micro controller and cheap also. The size of the box will be affected by the battery mainly. The size of the two antennas does not matter that much.
          Worst case they will need some help to optimise the two antennas. The volume of GSM modules and 2400 MHz modules is so BIG that all module vendors help with design in aid free of charge. Last but not least, that GSM antenna is radiating very well in comparison to out of the shelf embedded GSM antennas.

           

          We also do pcb traces but we license our design, and customers are very happy to pay for the excellence.

           

          Luciano, there is a marked for products and services that has to be paid and there is a market for openness and open source as well. Linux is good example for this. Linux you will find on tons of servers hidden behind concrete walls and fire walls. You can not see the OS, but it is already there. An Android has a Linux kernel. Android has taken 25% of the smart phone market within 2 years.

          Behind a Meego of Nokia and Intel is a Linux kernel 2.6.33 as well.

          Android is the opposite of Apple OS. Apples OS is closed and bundled with a piece of hardware always. The Open Handset Alliance has already 78 members.

           

          Innovating in the open
          "Each member of the Open Handset Alliance is strongly committed to greater openness in             the mobile ecosystem. Increased openness will enable everyone in our industry to             innovate more rapidly and respond better to consumers' demands. Our first joint project             as a new Alliance is Android™. Android was built from the ground up with the             explicit goal to be the first open, complete, and free platform created specifically             for mobile devices."
          Source Open Hand Set Alliance: http://www.openhandsetalliance.com/oha_overview.html

           

           

          Hope that you and other players in the industry stop putting different  antenna designs on the same box and also wake from this dream world  where knowledge and expertise become a commodity offered for free.

          Steve and Bill had hopes too. Steve has lost market share in smart phones. Bill as as well.

          http://files.techknots.com/mobiles/wp-content/uploads/Android-iOS-Market-Share.jpg

           

          The graphic is showing the share of mobile web only. On the CES in Las Vegas I have seen several "Smart Car" applications like Continental AutoLinq.

          If I counted right it was at least for automotive suppliers on Android. Non was on Apple OS.

           

          http://www.conti-online.com/generator/www/com/de/continental/presseportal/themen/pressemitteilungen/3_automotive_group/interior/img/img_2009_06_02_auto_linq_p1_de.jpg

           

          A free of charge antenna design, very detailed expained, including all parameters and description for a 868 MHz loop antenna you can download here:

          http://www.muehlhaus.com/files/Application%20Note%20-%20Analysis%20of%20an%20868%20MHz%20Loop%20Antenna.pdf

          • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
            Luciano Cesar Alakija Palma Newbie

            Hi Harald,

             

            The issue is not misleading the customer but to not acknowledge that in order to have a good antenna menas more than an antenna that "works". We are talking about efficiency and when the efficiency matters there is a competition for a very limited resource that is the frequency spectrum. And when you say that you have a design off the shelf you are actually misleading potential custumers who believe that the antenna is a device itself that does not have any relationship with the environment where it is located. You can start from some guidelines, this is no problem, but as stated by one of my references on this marke, "the reason why antenna design is considered as black magic throughout the world is because it takes hours of experimental testing to design the right antenna for your customer needs". This time cost and this cost should be covered unless you really want to do it for free... (it's countersence, indeed)

            The one who will come out with a universal antenna design will be able to retire in one of those paradise island…There are many reasons why antennas should be given more consideration but at the end of the day, just ask yourself:

            -          Did you experience being stuck at a restaurant waiting for the payment terminal to connect to the network ?

            -          Did you experience downloading data on your phone on WIFI and communication got cut before the end ?

            -          Did you have to reboot your GPS receiver 3 times before it locks on satellites in a blue sky area?

            -          Did you try to have an interview over the phone and got dropped calls 10 times in a row as you were walking by outside or in your house ?

            -          Did you often empty your handset battery in 2 hours in standby mode or in 45minutes talking over the phone ?

            -          Did you already miss the subway as your embedded NFC antenna was so poor that you could not pay to open the gate in Tokyo ?

            -          Did you try to move your Cordless home telephone to any parts of the house to avoid any noise while you are talking ?

            -          Have you ever managed to watch a complete movie on a CMMB/DVBH equipped handset or tablet ?

            …..that could explain why dealing with antenna expertise is the key to successful budget link for M2M or any other system …

             

            Now regarding an open source approach

            Luciano, there is a marked for products and services that has to be paid and there is a market for openness and open source as well. Linux is good example for this. Linux you will find on tons of servers hidden behind concrete walls and fire walls. You can not see the OS, but it is already there. An Android has a Linux kernel. Android has taken 25% of the smart phone market within 2 years.

            Behind a Meego of Nokia and Intel is a Linux kernel 2.6.33 as well.

            Android is the opposite of Apple OS. Apples OS is closed and bundled with a piece of hardware always. The Open Handset Alliance has already 78 members.

             

            you are again mixing two different concepts... and the success of open source is not only the fact that it's open, but the fact that it has a platform that incentives and help developers on their coding and application development. And not to mention that the principles of the antenna are quite different from the OS /SW development market... Personally I am supporting open mobile allience and all it's virtus in favor of the diversity of applications. But for antenna... sorry, you are not looking to this kind of diversity applications, you have to use your imagination to work on some tough challenges, like the miniaturization of devices at thesame time the device must cover have multiples bands.  if you install an application that is not ok, you can just unistall it... but you can not unistall an antenna... antenna is a basic essencial system on the device and it must be considered as a mission critical product. I am sure you should know that mission critical market is oriented to performance and eficiency instead of just price. Maybe today you (and your customers) do not see how critical is to have a design that fits and has the maximun performance, but, someday, not so long from now you will understand.

            • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
              Harald Naumann Expert

              Hi Luciano,

               

              The question was "Why to pay for an embedded GSM antenna if you can get the antenna for free?" and not related to antennas with small bandwidth like WIFI, GPS or NFC. About antennas with small bandwidth I would like maybe to come back later.

               

              Please feel free to simulate an inverted F antenna like in the picture published in beginning with the demo version of http://www.empire.de/ or the simulation software you already own. If you like you can select the Epsilon R of ABS for the plastic box as well. If you simulate it, then you will see that you get a reasonable antenna effiency.

              BTW, please remember that mobile phone companies like Siemens bought by BenQ or Nokia had their R&D in Germany. http://www.empire.de is a German product too.

              Some of my customers already own antenna simulation software and others will place orders for simulation, but a lot of them have no coin left for antennas in mass production. Size is often not a problem. Antenna efficiency is a topic and mentioned in my blog at www.gsm-modem.de/M2M and other places. The Antenna efficiency is saving the battery in several applications.
              As soon I have a minute left I will make a drawing of a Quad GSM antenna public, that offer 70% to 90% antenna effiency in simulation and already measured in 3D.

              We all know what we are doing. Misleading starts with placing an order with a supplier or online distributor that does not care on anything. If customers will create a device around an antenna structure that already was used before, then the chance with some advice is high to pass the necessary approvals.  What will happen without or wrong advice to customers that will read this blog post? Please note, that I will make several design mistakes I have seen last 15 years in another blog post public.

              The real big players, which I am talking, too are hiring developers for antenna design and group leaders for antenna design. They will not need advice for antennas of you and me. I am addressing with this blog post to the small accounts of 5000 to 50000 antennas only. The students and hobbyists maybe can use the software licenses at university or the 30 day limited versions as well. 

              Please note, that customers of mine in range of 1 to 100K are placing orders for antennas with me. I am able to give advice for out of the shelf antennas and antennas embedded in the PCB as well.  The get a solution based on RF module or RF chip plus antenna and part like micro controllers as well. Some kind of uC have to generate the data, that will be forwarded to the RF module or RF chip and will end by transmitting of the antenna.

               

              Will you stay at CeBIT in Hanover this week too? Do you will stay at Hanover Industry ?

              CeBIT http://www.cebit.de/home

              Hanover Industry http://www.hannovermesse.de/en/about-the-trade-show/facts-figures/profile

              • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
                Harald Naumann Expert

                As mentioed before  free of charge antenna design,  including  all parameters and description for a 868 MHz loop antenna you can  download here:
                http://muehlhaus.com/wp-content/uploads/2011/06/Analysis-of-a-868MHz-loop-antenna.pdf

                 

                The antenna simulation was done by using of software Sonnet.

                 

                Picture of the 868 MHz PCB loop antenna:
                868-mhz-loop-antenna.jpg

              • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
                Luciano Cesar Alakija Palma Newbie

                Hi Harald,

                 

                Size of the embedded antenna is always an issue since pcb board also has a cost.

                When you say the antenna is for free, actually you are not considering the space occupied by the antenna on the pcb (including clearance area). This space has a cost and PCB cost sometimes is higher them an standard antenna cost for cellular (824 MHZ).

                You also have a lack of flexibility. You can not move the antenna to other possible positions. You will always have to redesign for a new product which is costly, takes time to TEST, RETEST, TUNNING (remember that simulation has to be validated with real measurements) and it's not the best approach especially on smaller volumes as you mentioned.

                 

                As specialists and antenna focused we start our offer with of-the-shelf cellular embedded antennas for M2M like:

                P522306 or P522309: Cabled + connector version as the document attached: if interested, please do not hesitate to contact us: this version fits for designs using modules with connectors.

                 

                For solderable modules, you can take advantage of

                P522304  and P522303 with successful integrations and making devices successfully on OTA requirements.

                 

                Please, I also invite you to compare these models with the size of the antenna you propose and the area occupied by it.

                 

                It's always a trade-off between cost, size, expected efficiency (including TRP and TIS minimum requirements) and positions for the antenna. When you say to customer that he does not need to pay for an embedded antenna you are just referring to one of the variables (this is what I consider misleading).

                 

                So the answer to your question:

                Q: Why to pay for an embedded GSM antenna if you can get the antenna for free?"

                 

                A: Because the free/cheaper may become very expensive (in practice).

                 

                 

                To justify this, I include below some real experiences shared on his same forum:

                 

                 

                - From thread: http://m2m.com/message/1077

                "....

                Two key rules to remember with operator certification: 1) use a pre-certified module or else it could take up to 12 months and 2) work with an antenna design expert referred to you by your module vendor.  Antenna design flaws are the #1 reason why devices fail operator certification.  An example design flaw would be that the antenna is not position well enough to pick up a weak signal.  So if you are in an area where your phone shows 1 bar, the device wouldn't even see the network to establish a connection.  That's a very poor user experience and really cuts down the available coverage map.  Don't underestimate the antenna design.  This is one area where it worth spending money for a highly experience team to help you.

                ..."

                 

                - From thread: http://m2m.com/message/1077

                "

                Hi Mike,


                Are you referring to the Antenna Performance? This is extremely important to the Carriers. The requirements, since the first OTA test plan was installed, have increased over the years. With regards to certification, it is a PTCRB requirements for GSM 850/1900 and UMTS 850/1900 bands to be tested. Desense measurements are also required if cellular and WLAN are operating simultaneously. This is called our in the new CTIA CWG Test Plan (Converged Devices).

                 

                Many customers overlook the importance of antenna type and placement (configuration) and therefore have issues when they enter a lab for Antenna testing. Best to consult with an antenna manufacturer or any consultants or design centers that assist with this.

                 

                - Mike

                "

                 

                - From thread:http://m2m.com/thread/1009

                "

                John, antenna issues are probably the most challenging problem for engineers new to wireless design.  To give you an example, I was working on a GSM product for the USA market.  We had the hardest time getting through att certification.  They kept telling us the antenna design was not good enough, even though we never really experienced trouble establishing a connection.  The issue was that the antenna couldn't pick up a connection when the network signal strength was low.  So while my phone had one bar, the device didn't see the network at all.  Our redesign took over four months and we missed our launch deadline.  it was pretty brutal.

                 

                If you're serious about building a connected device, I strongly encourage you to hire an antenna design firm.  These guys know know what their doing.  Or at the very least hire an experienced antenna design engineer.  It will save you tremendous time / money in the end.

                "

                 

                 

                And also industry

                 

                Antenna Fundamentals from AT&T, created exactly because this is one of the bigggest reason for certification flaws.

                 

                Also from AT&T : http://www.att.com/edo/en_US/pdf/HWDevelopmentBestPractices.pdf

                at&t.png

                 

                hope this helps clarify the answer.

                 

                 

                Luciano Alakija

                Director Sales, Marketing and Tech Support - Latin America

                lalakija@ethertronics.com

                skype: luciano.alakija

                Mobile: 55 11 8402-9769

                Fixed/Fax: 55 11 2339-9769

                www.ethertronics.com

  • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
    Harald Naumann Expert

    The posted data sheets are marketing data sheets only. If I got the right data sheets of the antenna you mentioned by a friend, then there is a need of 12 mm from PCB boarder to the boarder of the ground plane. The structure I posted has a recommend distance of 10 mm. That means it is already smaller.
    Yours was tested on 50 mm x 80 mm = 4000 mm PCB including space for antenna and my one was tested on close the same size of PCB. By my one I can balance the bandwidth of the antenna by playing with the gap between the ground plane. For Europe I can make is smaller, because the bandwidth here is smaller.

     

    BTW, I own the documentation for the PTRCB, AT&T and Vodafone air approval.

     

    Even if my PCB is 2 mm longer then yours, then we talk about a 2 mm x 40mm bigger PCB. Maybe we talk about nothing, because I will not matter by a lot of 50 PCB (40 mm x 100 mm or 40 x 102 mm). You never can use the full size of FR4 plate.
    Let us assume my PCB is really 5 US cent more expensive, the there are the costs for pick and place and soldering of yours. My one is already a part of the PCB.

     

    It is much cheaper, maybe already smaller and will pass the PTCRB, AT&T and Vodafone air approval. BTW, it is just one out of 3 selected antenna shapes I like to use. There are close to 100 on my hard disk. A lot of them have a complex shape and needs bending. list

     

    A list of minimum recommended approvals I made public two or three years ago here.http://www.gsm-modem.de/ptcrb-fcc-rtee.html .
    And before I forgot to mention it: I guide lined European M2M projects where the antennas has passed the approval in laboratory in California in the past.

    Anyhow, are you able to offer an SMT mounted GSM antenna for USD 0,05. Not more 5 Cent including pick and place plus soldering. If you can, then just help with an offer to harald.naumann (at) gsm-modem.de . I will forward it to my business friend and recommend placing the order for the 30000 antennas with you.

    • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
      Luciano Cesar Alakija Palma Newbie

      Hi Harald

       

      If your friend become our customer someday he will receive a complete application note for any antenna we have.

      And I am sure he will see all other variables (size, performance, position, applications, besides cost) are really important to have a good wireless M2M device.

      We are quite serious about the data we publish. Performance of the datasheets is taken directly from the measurements we do on our chambers. And the measurement is done after the design and after simulation. We have our propietary simulation tool, but this is not enough. We do measurements not only on our demoboards, but also on customer devices to guarantee he will have an optimal product. This is part of ur value.

       

      Regarding size, the area occupied by our SMT antenna P522304 is exactly it's size: 35.0 x 9.0 x 3.2 mm, no more than this.

      The standard antenna has also a 10 mm distance from the board edge, and the clearance area is exactly it's antenna size. These are some advantages of our patented IMD design. We are talking about only 35 x 10 = 350 mm2 of pcb area.

       

      In the worst case, and only if you reduce de board size to below the lambda/4 we recomend a clearance of 12 mm. But this means only 420 mm2. Actually this is to still have a global pentaband performance (all 4 bands in 2G and in 3G as well). Of course, if only European market is considered, you may relax some of the constraints, which makes it even a better choice.

       

      And actuallly it will be quite interesting to see the performance of the embedded antenna AFTER you enclose the board on a plastic case.

      We have tests on this with the performance reaching 50% and over even on these worst (and quite real) conditions.

      shield.png

       

      So SMT version is SMT because other components on the board are also SMT. We have a good demand for it our customers welcomed this method because it's received in tape and reel and mounted like other components.

       

      BTW: an antenna that is already part of the pcb is a risk. The material dielectric constant is quite sensitive to small changes on the material which is quite common to occur with pcb suppliers... so you need to be careful about the pcb supplier quality process and make sure the customer will always receive the same material over a long period (this seems more sunk cost...). I also have real examples when the antenna was completely detuned after some process variation or supplier changed...It's not universal and is quite sensitive to changes.

       

      Please, fell free to put your business friend in contact with me, I can talk to our European Design Center in Copenhagen. Even you (after signing an NDA, of course) are invited to stop by this DC. We have other 7 Design Centers around the world.

       

      Again, hope you understand that your 100 designs are all possible solutions. For each customer there is a specific condition, constraint. If you have the ability, technical equipment, resources and time to really make a good antenna for him withouth charge for it, do it!

       

      But

      1) Sonner or later the market will understand the difference on different designs. Being your designs good designs, they will survive.

       

      2) just take care because if your customer is using a copied design. He may not be happy with a bill due to IP violation.

      Again, the cheaper may become expensive.

       

      3) Everybody and any customer always asks to have the best for the chepeast. But I would rather guide him on the trade-off between cost and results than accept a "good enough" approach for antenna. This is a big risk for any wireless device, botho on test / certification anf on field proof.

       

      Best regards,

      Luciano

      • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
        Harald Naumann Expert

        Hi Luciano, before I started this blog post I already had a request for 50000 GSM antennas as a structure in the PCB. It is a device in a plastic box where I can select the type of the boy, the size of the box and the type of the antenna. They only what I can not change is the target price. The target price is USD 0 for the antenna. So if you are able to deliver for USD 0, then we can talk.

        During we talk I got another request for a GSM antenna as a structure inside PCB. The plastic box is ready. The prototype is working with an antenna structure that is in my opinion wrong. It could be much better. I made a proposal last days and a business friend will make them an offer for optimisation.
        Last but not least I will make them an offer for a PCB antenna that will fly with a distance of 8 mm offer ground plane. It will be a planar inverted F antenna with antenna effiency with 70% to 90% for GSM 850, GSM 900, GSM 1800 and GSM 1900.

         

        I will give them the freedom to:
        1. go ahead with the PCB structure they already use
        2. move to my PCB antenna structure proposal and to get a better a much better performance
        3. select the planar inverted F antenna

         

        Option 2 costs will help them with an antenna free of charge. They have just to spend money once a time for optimisation. Option 3 is not for free but still cheap, because it is an PCB structure only.

         

        BTW: an antenna that is already part of the pcb is a risk. The material  dielectric constant is quite sensitive to small changes on the material  which is quite common to occur with pcb suppliers...

         

        For me there is no risk. Germany is Automotive country. It is easy to find partner with high quality standards. The R&D centres of former Siemens mobile phone and Nokia are close to my home. The R&D of former Ericcson is even closer. At their show case you will find samples of old GSM mobile phones.


        Again, target price for antenna in five of my latest projects is 0 USD. If a customer want 0 USD, then they get 0 USD. If developers ask for advice how to design a M2M device cheap and powerful, then I can recommend everybody to select a partner that will be able to give advice on GSM module, GSM antenna, GPS antenna, GPS module and enclosure in a very early stage. The concepts for my customers contains if they like RF modules, antennas, enclosures, batteries, power supply, micro controllers, SIM card holders (or SIM on Chip). If they like they can get all parts from one hand. If they want antennas for free, then they get it for free. If they wish to stay with the micro controller they like and used before, then I give them the freedom to do that.

        • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
          Harald Naumann Expert

          Quick chat by Skype today with a customer that has used the structure published here a while ago. I will keep you posted on the further steps.

          [15:23:28] Customer: Hi harald

          [15:23:37] Customer: so sorry for my missings replies
          [15:23:42] Customer: I'm really busy
          [15:24:09] Customer: but I would like to say thanks for the big support and specially for the GSM PCB antenna
          [15:24:20] Harald Naumann: Hi
          [15:24:34] Harald Naumann: No problem at all.
          [15:25:08] Customer: we made the PCB basing your information and we have reached almost the same signal quality than original external antena that is comming with the kit

  • Re: Why paying for an embedded GSM antenna if you can get the antenna for free?
    Harald Naumann Expert

    Email to  me:

    Thank you very much for your article http://m2m.com/thread/1751 .

    It was very interesting and informative.

    Please, if you'll have free time please answer my questions.

     

    On the figure is not clear where is the feed point. Where is the yellow line is attached to the red and green lines?
    HN: Red, green and yellow lines are on the same layer. The copper structure is one and the same.

    Do you have a more detailed picture?
    HN: Yes, I have a more detailed description as PDF file.

     

    Is the red and the green line is shorted to ground plane on the left?'

    HN: Yes, at left side it it shorted to ground. It is a IFA an inverted F antenna with two rods. The longer structure is for GSM 900 and the short is for 1800 MHz. If you search on Google, then you will find a lot of information about 2400 MHz IFA antennas.

     

    Is the length of the antenna depends on the thickness of the copper layer and the thickness of the FR-4?
    HN: You are right. FR4 has an Epsilon R of 4,2 in average.

  • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
    Harald Naumann Expert

    IoT M2M Cookbook abstract in the news

    April 2014 @ M2M Journal http://www.m2m-alliance.com/fileadmin/user_upload/pdf/m2mJournal/140402_M2M_Journal_low.pdf

    M2M IoT Cookbook 400x248 IoT M2M Cookbook abstract in the newsThe 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 of experience in the development and consulting wireless devices is included in all chapters. The integration of antennas has been paid special attention. The antenna is the key to success with any wireless application. The simulation, and the result, is a quad-band GSM antenna and is explained in detail.

    Each developer can easily copy the result without the use of mathematics. In the example of the vending machine, the self-made, integrated antenna not only saves the external antenna, but also the coaxial socket and installation as well. The same antenna can save the expensive SMT mount cellular chip antenna in a locating device and is easily adapted to the Epsilon R of the housing. Other sub-themes are power supply and choice of carrier (USSD, SMS, CSD, DTMF, GPRS) approvals. Typical mistakes of first-time users are addressed too.

    The developer selects the antenna design first and then builds the device around the antenna. This results in a large cost saving for hardware and installation. At the vending project the estimated saving was 4,000 installations x $ 10 = $ 40,000. The integrated antenna with the optimised ground plane is so good that during redesign the switch and the coaxial socket to the external antenna were excluded.

    ABOUT THE AUTHOR HARALD NAUMANN

    More than 25 years in radio communication with a focus on wireless data communication. Today he is working with Future Electronics as a Field Application Engineer for wireless applications.

    Contact:
    Harald Naumann • Field Application Engineer for wireless applications •

    harald.naumann(at)gsm-modem.de •  www.gsm-modem.de/M2M/m2m_iot_cookbook/

    Origin text with photo: http://www.m2m-alliance.com/fileadmin/user_upload/pdf/m2mJournal/140402_M2M_Journal_low.pdf

    Many thanks again to the M2M Journal team for printing the abstract.
    Do not hesiate to ask for a copy of the IoT M2M Cookbook.

  • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
    JCrystal Newbie

    Just came across this. Thanks Harald however, this appears to be good for hackers/ham radio apps but hardly useful for real world multi-band cellular M2M devices. In your IoT cookbook you even explain why (tight domestic and international cert. regulations, industry requirements, power restrictions, TRP/TIS, SAR, etc. I would strongly suggest that any product designer seek out an established antenna design house particularly for products designed into custom enclosures or designed for a mobile application. My last product had 7 cellular band operation for worldwide coverage and the antenna could hardly be designed using a simple recipe.

     

    Buy the way, I have almost 40 years in product design, much of it with RF and I've been designing stationary and mobile M2M devices for the last 6 years. Some with cellular modules and some with discrete cellular chip sets.

    • Re: Why to pay for an embedded GSM antenna if you can get the antenna for free?
      Harald Naumann Expert

      Jack, the antenna is ready to copy and business partners of mine offer the tuning. Nevertheless, the simple shape is easy to tune on GSM 850/900 and GSM 1800/1900. Anyhow, the same company that made the simulation for my book, developed the multiband antenna as below:

       

      Embedded LTE antenna in detail