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<?xml-stylesheet type="text/xsl" href="https://devzone.nordicsemi.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>how to beacon between Smart mobile and NRF51 detect distance</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/53507/how-to-beacon-between-smart-mobile-and-nrf51-detect-distance</link><description>I am developing a beacon-related project, my nrf51 device needs to play beacon. Beacon will determine the distance from NR51-&amp;gt; Smartphone. If distance = distance I give, I will perform some action. So how to with only nrf51, only 1 smartphone can recognize</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Tue, 22 Oct 2019 13:07:50 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/53507/how-to-beacon-between-smart-mobile-and-nrf51-detect-distance" /><item><title>RE: how to beacon between Smart mobile and NRF51 detect distance</title><link>https://devzone.nordicsemi.com/thread/216183?ContentTypeID=1</link><pubDate>Tue, 22 Oct 2019 13:07:50 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:a6b12b78-fd95-45e3-9dd3-008a215e8b23</guid><dc:creator>Simonr</dc:creator><description>&lt;p&gt;Hi&lt;/p&gt;
&lt;p&gt;So maybe something like the &lt;a href="https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v12.3.0%2Fble_sdk_app_proximity.html&amp;amp;cp=5_5_8_4_2_2_16"&gt;ble_app_proximity &lt;/a&gt;example is what you&amp;#39;re looking for? It alerts the user when connected devices are too far apart and can, for example, use the battery service to transmit its battery level while connected.&lt;/p&gt;
&lt;p&gt;Best regards,&lt;/p&gt;
&lt;p&gt;SImon&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: how to beacon between Smart mobile and NRF51 detect distance</title><link>https://devzone.nordicsemi.com/thread/216116?ContentTypeID=1</link><pubDate>Tue, 22 Oct 2019 10:42:39 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:be3eb8f2-4ad8-4cfa-92b3-b9431076c530</guid><dc:creator>tran duc tien</dc:creator><description>&lt;p&gt;In fact, my project doesn&amp;#39;t need RSSI. the purpose is to determine the connection of the phone and nrf51, if it is connected, I will do something, if it is not connected I will do something, just like that, I have can create beacons but I don&amp;#39;t know how to check the connection between them? Are there any examples similar to it?&lt;br /&gt;thank you!&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: how to beacon between Smart mobile and NRF51 detect distance</title><link>https://devzone.nordicsemi.com/thread/216075?ContentTypeID=1</link><pubDate>Tue, 22 Oct 2019 08:12:30 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:75c1913a-999d-4878-87e0-635341776cdb</guid><dc:creator>Simonr</dc:creator><description>&lt;p&gt;Hi Tienpjo&lt;/p&gt;
&lt;p&gt;The nRF51 series does not support an accurate way of measuring the distance between a beacon and a phone. You can use the RSSI value of the last received packet in a BLE event as a rough estimate of how far away this is by using the &lt;a href="https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.s130.api.v2.0.1%2Fgroup___b_l_e___g_a_p___c_e_n_t_r_a_l___r_s_s_i___r_e_a_d___m_s_c.html"&gt;RSSI get sample&lt;/a&gt;, but I&amp;#39;m afraid this isn&amp;#39;t a great way of measuring the distance.&lt;/p&gt;
&lt;p&gt;In order to accurately measure distance, you&amp;#39;ll either have to &lt;a href="https://en.wikipedia.org/wiki/Triangulation"&gt;triangulate &lt;/a&gt;the distance from your phone to multiple nodes in a Mesh network, or use the &lt;a href="https://www.nordicsemi.com/Products/Low-power-short-range-wireless/Direction-finding"&gt;Bluetooth 5.1 direction finding&lt;/a&gt; (which phones don&amp;#39;t support as of yet) and only the nRF52811 and nRF52833 support that from our side.&amp;nbsp;&lt;/p&gt;
&lt;p&gt;Best regards,&lt;/p&gt;
&lt;p&gt;Simon&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>