This very compact panel 2.4/5.8 GHz multiple-input and multiple-output (MIMO) patch antenna is designed to operate with many manufacturers' enterprise-class 802.11n. TerraWave 333918 MIMO Patch Antenna, 6/7 dBi with RPSMA Plug Connector: Electronics Antennas: Amazon.com: Industrial & Scientific. Netgear 6000450 Mimo AntennaYou might have noticed your new wireless broadband modem for some reason has two ports to plug in an antenna. So which one do I use, and what on earth do I need two for? MIMO - Multiple In Multiple Out In this guide we're going to give you a basic understanding of MIMO technology, hopefully without getting too technical. If you're unfamiliar with how your mobile phone or wireless internet USB stick works you might wish to read first. Since the beginnings of radio technology we've become accustom to a mobile phone or UHF radio transmitting with a single antenna. This transmission travels through the air and is received by a much larger antenna on a phone tower, which in turn rebroadcasts the signal to your intended destination. For transmitting a phone call this technology is simple and effective. Patch Antenna DesignHowever with the increasing demand for faster and more reliable 3G wireless internet, which works in the same way as a voice call, more complex methods of transmitting were needed. If you've been using 3G internet for a few years now you would have noticed the claimed top speeds rapidly increasing - starting around 3.6Mbps for the first series of mobile broadband 'sticks', to 7.2Mbps around 2007, to 21Mbps in 2008, to 42Mbps shortly after, and now 100Mbps with the 4G introduction in late 2011. Of course it's unlikely that you've ever actually experienced such blisteringly fast bit rates, but most people will have experienced a noticeable jump in speed when changing to a new modem. How do they make such incredible jumps in speed? Increasing speed is a tricky business - in the theoretical world the biggest factor limiting speed is bandwidth. Each phone tower has a given total width of frequencies it can transmit on, with each person that connects being allocated a small channel of a certain width. This means that each tower has a limited number of customers it can service before becoming congested. Patch Antenna ImpedanceSo the most obvious way to increase speed would be to give each customer a wider range of frequencies to transmit on, but this means less people per phone tower, which means building more phone towers, which is expensive! Instead, the first step in increasing speed is to exploit the other factors aside from bandwidth. 3G technologies like HSPA take advantage of digital modulation techniques like Quadrature Phase Shift Keying (and many other tricks) to increase the symbol rate, which is the second major factor that limits speed.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |