Please have a look at the reference designs section at the Trace Antenna PCB reference design, also you can have a look at the documents AN-B-027 and AN-B-036 for more information.
Hi, I have referred AN-B-027 Doc, there they have explained about Printed PCB antenna but we are looking for external coaxial antenna circuit so that we can connect external antenna to increase the range. Please suggest the reference design with external antenna connector
Most of the reference designs are using printed antennas, you can check the daughter boards of the expert kit that use coaxial antennas. But since you want a coaxial antenna on your device all you need is a 50 ohm stripline and a 50 ohm coaxial connector. You can find all the files in the Development kit tabs on the expert kit section.
An SMA antenna has a radiation efficiency of say -2dB in average. But depending on direction and elevation, it can be much less. In case of the the SMA antenna we deliver with the expert kit, it can be as low as -25dB (worst case).
Assuming an ideal antenna (0dB gain) and line of sight, no obstacles, the theoritical range is more than 100 meters. The path loss is 92dB, and this is covered by the 580 link budget.
If the antenna is such that we have -25dB gain (link budget = 67 dB) the range is limited to about 15 meters.
Dear MT_dialog, Thanks for your information, There is a two capacitor near to the SMA Connector ,in Expert Kit, Daughter Board schematic. Those capacitors value have been mentioned as TBD. Please let me know the value of those capacitor(C14 and C15).
Dear MT_Dialog, 有什么constraint on PCB trace width and trace length which is going to SMA Connector for External Antenna because it will act like transmission lines which may further increase or decrease the impedance.
Yes, the PCB trace running from the RFIOp pin must be close to 50ohm, if this is done neatly (no abrupt changes in the trace, not changing layers, a solid ground plane under the trace), the length is not critical. The width is determined by the board properties and thinkness (distance to ground layer). A zero ohm resistor is not required. Also a shunt inductor close to the RFIOp pin must be applied. 3.3nH for the WLCSP, and 3.9nH for the QFN packages, thats missed in the expert kit daughter boards, it came a bit later, you can check the 583 pro daughter board in order to check the placement of the inductor with a coaxial antenna.
Dear MT_Dialog, 谢谢你的建议。 Recently we have purchased IoT Sensor Kit which is having Printed antenna and we have tested the board with mobile phone, hardly it supports 5m range but we need further more range . so in our customize board we have planned to have external SMA Connector instead of PCB antenna. what will be the maximum range it can support without connecting External antenna but board will have SMA connector provision. Consider Line of Sight and No obstacle case.
The connector itself will not radiate much, from experience, the connected PCB trace will radiate more. How far depends on the PCB structure, length of trace, etc. But i dont think that will reach over 1 meter.
Hi Karthikeyan S,
Please have a look at the reference designs section at the Trace Antenna PCB reference design, also you can have a look at the documents AN-B-027 and AN-B-036 for more information.
Thanks MT_dialog
Hi,
I have referred AN-B-027 Doc, there they have explained about Printed PCB antenna but we are looking for external coaxial antenna circuit so that we can connect external antenna to increase the range. Please suggest the reference design with external antenna connector
Hi Karthikeyan S,
Most of the reference designs are using printed antennas, you can check the daughter boards of the expert kit that use coaxial antennas. But since you want a coaxial antenna on your device all you need is a 50 ohm stripline and a 50 ohm coaxial connector. You can find all the files in the Development kit tabs on the expert kit section.
Thanks MT_dialog
Hi MT_dialog,
Thanks for your valuable inputs.
How much range will be covered by external coaxial Antenna in Line of Sight consider without obstacles.
Hi Karthikeyan S,
An SMA antenna has a radiation efficiency of say -2dB in average. But depending on direction and elevation, it can be much less. In case of the the SMA antenna we deliver with the expert kit, it can be as low as -25dB (worst case).
Assuming an ideal antenna (0dB gain) and line of sight, no obstacles, the theoritical range is more than 100 meters. The path loss is 92dB, and this is covered by the 580 link budget.
If the antenna is such that we have -25dB gain (link budget = 67 dB) the range is limited to about 15 meters.
Thanks MT_dialog
Dear MT_dialog,
Thanks for your information,
There is a two capacitor near to the SMA Connector ,in Expert Kit, Daughter Board schematic. Those capacitors value have been mentioned as TBD. Please let me know the value of those capacitor(C14 and C15).
Hi Karthikeyan,
这些电容器是天线匹配所必需的（TBD代表待定），电容器的值取决于要放置在电路板上的天线，在expert kit dev电路板上，不放置这些电容器帽，因为您可以放置所需的任何天线。如果你要放置的天线是50欧姆，你就不必放置任何匹配的电路。
Thanks MT_dialog
Dear MT_dialog,
谢谢，
Is Zero ohm resistor required if we place antenna with 50 Impedance.
Dear MT_Dialog,
有什么constraint on PCB trace width and trace length which is going to SMA Connector for External Antenna because it will act like transmission lines which may further increase or decrease the impedance.
Hi Karthikeyan S,
Yes, the PCB trace running from the RFIOp pin must be close to 50ohm, if this is done neatly (no abrupt changes in the trace, not changing layers, a solid ground plane under the trace), the length is not critical. The width is determined by the board properties and thinkness (distance to ground layer). A zero ohm resistor is not required. Also a shunt inductor close to the RFIOp pin must be applied. 3.3nH for the WLCSP, and 3.9nH for the QFN packages, thats missed in the expert kit daughter boards, it came a bit later, you can check the 583 pro daughter board in order to check the placement of the inductor with a coaxial antenna.
Thanks MT_dialog
Dear MT_Dialog,
谢谢你的建议。
Recently we have purchased IoT Sensor Kit which is having Printed antenna and we have tested the board with mobile phone, hardly it supports 5m range but we need further more range . so in our customize board we have planned to have external SMA Connector instead of PCB antenna. what will be the maximum range it can support without connecting External antenna but board will have SMA connector provision. Consider Line of Sight and No obstacle case.
Hi Karthikeyan S
The connector itself will not radiate much, from experience, the connected PCB trace will radiate more. How far depends on the PCB structure, length of trace, etc. But i dont think that will reach over 1 meter.
Thanks MT_dialog
亲爱的先生,
实际上我们的要求是，至少BT设备应该支持30米，而不连接外部天线，所以哪种天线电路更好，要么是PCB天线，要么是外部同轴开关（不连接外部天线盒我需要）。是否有任何外部电路会增加范围，因为我们使用TI传感器标签进行了测试，但没有连接外部天线，它会上升到30米（没有视线和障碍物情况）（请参考示意图：http://www.ti.com/lit/df/swrr134/swrr134.pdf)在原理图中，在射频侧有一个外部电路，它是用于增加范围还是用于天线阻抗匹配。
再澄清一点，覆盖范围取决于内部处理器设计，或者我们可以通过添加外部电路来增加范围（除了外部天线连接，因为我们的电路板尺寸非常小（类似于dialog IoT传感器板），我们不想保留外部天线）。
Hi Karthikeyan S,
Please check your other post regarding the IoT sensorhttp://support.dialog-semiconductor.com/iot-sensor-kit-range.
Thanks MT_dialog