Banana Pi BPI-R4 Wifi 7 BE14 - Pigtails and Antennas

[SpectreDev]

What’s the best antenna I could buy

[Thanks]

I think these pigtails with right angle RP-SMA connector and RG178 cable would be better for BPI-R4 and BPI-R3 than the regular ones, maybe the length of the cables should be 20 cm for BPI-R4 and 25 cm for BPI-R3:

AliExpress Links:

• RP-SMA F Right Angle: TUOLNK (5PCS) - BEVOTOP (2PCS) - BEVOTOP (10PCS)

  

To pass the antenna wires under the board and make it look nice and clean, as @as_jt shows here:

Banana pi R3 fan with PWM

My cooling system. [20230304_220045]

[Thanks]

@SpectreDev

What’s the best antenna I could buy

About the tri-band antennas mentioned above, I don’t know, someone has to buy the antennas and test them in the real world, maybe @VA1DER can find out by looking at the datasheets.

According to @VA1DER the order of the antennas from the best to good, would be like this:

Dipole antenna

1. Taoglas: GW.52.A153 ---------------------------------- (Datasheet)
2. TE Connectivity: ANT-W63WS6-IPW1-RPS ----- (Datasheet)
3. KYOCERA AVX: X1005800-W5DRMB ------------- (Datasheet)
4. Amphenol RF: ST1228-40-501-A ------------------- (Datasheet)
5. Taoglas: GW.59.3153 ----------------------------------- (Datasheet)
6. Joymax: TWX-614XRS3B ----------------------------- (Datasheet)
7. Joymax: TWX-180BRS3B ----------------------------- (Datasheet)
8. Joymax: TWX-721XRS3B ----------------------------- (Datasheet)
9. ALFA Network: ARS-NT5B7 -------------------------- (Datasheet)

Monopole antenna

• Siretta: DELTA37/SMAM/RP/S/36 ------------------- (Datasheet)

.

I’ve added one of the best monopole antennas in case anyone wants to test it.

Information about dipole and monopole antennas:

• What is the difference between a monopole and dipole antenna?
• What is the difference between a dipole and a monopole antenna? Which one is better for WiFi communication, and why?
• What are the advantages of a dipole antenna over a monopole as dipoles are more commonly used?
• Monopole vs Dipole Antenna
• Difference between Dipole Antenna and Monopole Antenna
• All About Wireless: Antenna Types and Characteristics
• Dipole or monopole?

@Quora Bot

A monopole antenna and a dipole antenna are both common types of antennas used in various applications, including WiFi communication. Here’s a breakdown of their differences and advantages:

Monopole Antenna

• Structure: A monopole antenna consists of a single radiating element, typically mounted above a conductive surface (ground plane). It is essentially half of a dipole antenna.
• Length: The length of a monopole is usually a quarter of the wavelength (λ/4) of the frequency it is designed to transmit or receive.
• Radiation Pattern: Monopole antennas typically have an omnidirectional radiation pattern in the horizontal plane, meaning they radiate equally in all directions around the vertical axis.
• Impedance: They typically have an impedance of about 36.5 ohms, but when used with a ground plane, they can be matched to standard 50-ohm systems.

Dipole Antenna

• Structure: A dipole antenna consists of two radiating elements, each a quarter wavelength long, making the total length half of the wavelength (λ/2).
• Length: The total length is λ/2, and each arm is λ/4.
• Radiation Pattern: Dipole antennas also have an omnidirectional radiation pattern, but they tend to have a slightly different distribution of radiation strength, with nulls (areas of reduced signal) along the axis of the dipole.
• Impedance: A typical dipole antenna has an impedance of about 73 ohms.

Comparison for WiFi Communication

• Performance: Both antennas can be effective for WiFi communication. However, dipole antennas generally offer better performance in terms of gain and bandwidth, especially in environments with obstacles or interference.
• Size and Design: Monopole antennas are often smaller and easier to implement, making them suitable for compact devices (like mobile phones and some WiFi routers). Dipole antennas can be larger and may require more space.
• Installation: Dipole antennas may require more careful positioning to optimize their performance due to their radiation pattern, while monopole antennas can often be easier to install.

Conclusion

For WiFi communication, the choice between a monopole and a dipole antenna depends on the specific application and environment. If space is limited and a compact design is necessary, a monopole may be preferable. However, for optimal performance, especially in terms of gain and coverage, a dipole antenna is generally considered better.

In practice, the decision may also be influenced by other factors such as cost, availability, and specific design requirements of the WiFi system being used.

@Quora Bot

Dipole antennas are often preferred over monopole antennas for several reasons. Here are some key advantages of dipole antennas:

1. Radiation Pattern: Dipole antennas typically have a more uniform radiation pattern, often providing better omnidirectional coverage in the horizontal plane. This makes them suitable for applications where a consistent coverage area is needed.
2. Efficiency: Dipole antennas can be more efficient in certain configurations, especially when properly matched to the feed line. They can radiate energy more effectively because they do not rely on ground reflection for their radiation pattern as much as monopoles do.
3. Bandwidth: Dipole antennas can offer wider bandwidth compared to monopole antennas, especially when designed with specific materials or configurations. This makes them suitable for applications requiring a range of frequencies.
4. Impedance Matching: Dipole antennas typically have a higher feed point impedance (around 73 ohms for a center-fed dipole) compared to monopoles, which can simplify impedance matching with certain feed lines.
5. Ground Dependency: Monopole antennas require a good ground plane for effective operation, as they rely on the ground for reflected signals. Dipoles are less dependent on ground conditions, making them more versatile in various environments.
6. Construction and Size: Dipole antennas can be easier to construct and deploy in certain situations. They can be made from simple materials and can be scaled for different frequencies without significant complexity.
7. Polarization: Dipole antennas can be easily configured for different polarizations (horizontal or vertical) by changing their orientation, providing flexibility for specific communication needs.
8. Reduced Interference: In some cases, dipole antennas can exhibit reduced interference from ground-based noise sources compared to monopoles, making them suitable for sensitive applications.

In summary, while both dipole and monopole antennas have their applications, dipoles offer advantages in terms of radiation patterns, efficiency, bandwidth, and versatility, which often makes them the preferred choice in many scenarios.

@Sahir Ahmed

Dipole is better for WiFi communication as external dipole antennas can be controlled directionally. Thus, if the antennas are perfectly positioned, they can provide a stronger signal in a given direction. Directionally controlling signals works best outdoors where there are few obstacles to signals.

@Imam Hasan

As it has been pointed out monopole antenna acts as dipole virtual antenna after getting nearby reflections. The other advantage of dipole antenna is electromagnetic field pattern, which covers far more area than monopole antenna. Dipole coverage also tends to be less lossy than monopole as well. Since, in dipole two poles always maintain different polarity, it takes half peak voltage (but same power) to produce same signal strength of monopole antenna.

[SpectreDev]

wow, theyre expensive, are they charging for 1 antenna or 2

[Thanks]

“Cheap is expensive”

The older ARS-NT5B dual band antenna from ALFA Network is cheap on eBay:

• 3 antennas for $14 (older model, not the new tri-band model)
• 4 antennas for $18 (older model, not the new tri-band model)

Maybe you can buy three ARS-NT5B dual band antennas for the 2.4 GHz and 5 GHz bands and three tri-band antennas mentioned in the next post for the 6/7 GHz band.

And if you want the best antennas for all bands (2.4 GHz, 5 GHz and 6/7 GHz) then buy 6 good tri-band antennas, although it will be more expensive.

[VA1DER (Kurt Fitzner)]

@Thanks

• TE Connectivity: ANT-W63WS6-IPW1-RPS ----- (Datasheet)
• Taoglas: GW.52.A153 ---------------------------------- (Datasheet)
• ALFA Network: ARS-NT5B7 ------------------------- (Datasheet)

The first two have good data sheets. The third has a very weak one.

Antenna 1 and 2 look to have similar characteristics. Antenna 2’s data sheet is more comprehensive and includes data on the ground plane in two orientations. For our purposes, the closest match is “On 9x15 ground plane bent”. Antenna 2 appears to be a little superior to 1 for 2.4GHz efficiency with ground plane. It’s hard to compare them at 5 and 6 GHz because antenna 2 splits their data into different board orientations, and antenna 1 doesn’t. That said, I suspect antenna 1’s orientation is 15x9, or at least it looks that way in the diagram, and if that’s the case then antenna 2 appears to have somewhat better efficiency at 5 and 6 GHz also.

Antenna 3 only publishes VSWR data and it appears to be free-space measurements only, so it’s really hard to compare.

@SpectreDev

wow, theyre expensive, are they charging for 1 antenna or 2

When someone goes to all the work to create proper data sheets free-space and ground-plane VSWR/Return Loss/efficiency charts and proper 3d radiation patterns, that bumps the price up.

[adri]

Why would you need tri-band antenna’s? The BPI-R4 uses 3 dual-band antenna connections for the combined 2.4/5 GHz band and 3 single band antenna connections for the 6 Ghz band. I would invest in 3 good dual-band 2.4/5 GHz antenna’s and 3 good single band 6 GHz antenna’s.

[Thanks]

Thank you very much for your comment and your help.

[SpectreDev]

Yeah ok, I’m convinced on buying 6 of antenna 2, as the antennas that comes with the wifi card are horrible, the barely work on the 2nd floor of my house

[SpectreDev]

Thanks for the help, I appreciate it, gonna buy the rg178 cables from Tuolnk and the 6x antennas from taoglas

[Thanks]

If it’s not too much trouble, could you give me your opinion about this older tri-band antenna from Taoglas compared to the previous ones:

• Taoglas: GW.59.3153 ----- (Datasheet)

[VA1DER (Kurt Fitzner)]

The dip in return loss falls outside the 2.4GHz frequency range on the board orientation that best matches the R4, which is unfortunate. It may be a little poorer performing at 2.4GHz. I like how closely the efficiency curves match between straight and bent (bent tends to be worse), but they don’t publish those curves broken down by board orientation. All the board orientation breakdowns are just return loss at 2.4GHz. So it’s really hard to compare. What I see looks good, and if those efficiency numbers pan out it’s a good antenna. But it’s hard to know how it will perform on an R4 bent.

[Thanks]

Thank you so much for sharing your wisdom.

[SpectreDev]

So best to go for the other one I guess

[Thanks]

As far as I know, and I may be wrong, both tri-band dipole antennas from Taoglas are good, but the “gain” of the older antenna is 3 dBi on most bands and the “gain” of the newer antenna is 5 dBi on most bands; the one with higher gain ratings will give you a little extra range, but you pay more for it.

Information about antenna “gain”:

• How Antenna Gain affects Range in FPV
• dBi, dB, dBm dB(mW): Defined, Explained and Differentiated
• Antenna Gain Explanation
• To Gain or Not to Gain…That is the Antenna Question
• 8dbi vs 5.8dbi vs 3dbi - Which cables & connectors to choose to reduce signal loss?

@VA1DER

First, remember that about 99% of the antennas that say they are 5dBi gain are really just dipoles that have an actual gain of 2.14dBi. So don’t be too trusting of those dB gain numbers you see.

Next remember that “gain” in an antenna isn’t actual gain in the sense you get from an amplifier. It’s shaping/sensitivity in a particular direction at the expense of loss in another. The “i” means isotropic, which is a theoretical antenna that is a perfectly omnidirectional radiator. 5dBi means in one direction or plane the antenna radiates more strongly by 5dB, and in other areas it radiates 5dB weaker. Here is the radiation pattern of a standard dipole, looking at it from the side. Don’t look at the ring numbers, the outer ring is actually set to 2.14dBi, which is the actual gain of a dipole.

You will naturally get more than the normal 2.14dBi dipole “gain” just because you have more than one dipole. As I mentioned, two dipoles tend to focus the signal not just in the squished plane of a single dipole, but also linearly (like the CB radios example).

My advice is to use normal dipoles and if there is extra shaping you want to do, arrange the antennae in such a way as their mutual emission pattern shapes the signal.

@VA1DER

For gain, as mentioned, MOST of the gain numbers in ads on Ali Express or even Amazon are fairy tales. A dipole gives 2.14dBi gain. A thee element colinear might give 5 or 6dBi gain but will be 40cm long. To get the 8-12dBi gain claimed by some, you’d need a colinear antenna that’s a good 1m long. These exist, but aren’t really practical.

The gain of those antenna shapes the signal to be more and more like a frisbee (a dipole is like a donut), flattening it out. Maybe good for single-floor, but very strongly polarized, and harder to make efficient and broadband.

I tend to stick with normal dipoles

[SpectreDev]

Cool thanks, the stock ones are horrible I can’t even get a signal upstairs in my house and if I do it’s running at 5mbps lol, compared to my router provided by isp that can do 300mbos in my weakest room

[totkeks (Norman Dankert)]

I’m using these https://www.amazon.de/dp/B09V4YXMZN as I needed longer pigtails. They seem to work so far, but haven’t done any speedtests or analysis on the signal quality yet.

[Betonmischer]

I’d like to share new data about the Antsym 5 GHz antennas that I’ve purchased as a replacement for the stock BPI ones. Now that I’ve done signal measurement (at 2.5 meters in direct line-of-sight) it looks like they’re not any better after all. I guess that does it for cheap antennas for me. I’ll try to get my hands on those rather expensive tri-band antennas from Taoglas and report back on how they perform.

band	brand		router signal	NIC signal/noise	
5ghz	sinovoip		-15			-38/-77
5ghz	antsym			-14			-39/-74

6ghz	sinovoip		-25			-39/-76
6ghz	antsym			-27			-43/-75

[Thanks]

I think this is the correct way to place the WiFi and Cellular antennas on the BPI-R4 when you have a WiFi 7 module (BE14) and a 5G module (RM520N-GL) installed. It is recommended that the cable has the same length for all antennas on each radio, maybe 20 cm cables (IPEX-1) for all WiFi antennas (mentioned above) and 10 cm cables (IPEX-4) for the Cellular antennas:

Antenna Placement #1
--------------------
2/5g         6g
Leave this space between WiFi antennas or use it for cellular antennas
6g           5g
2/5g         6g

.

Antenna Placement #2
--------------------
5g           6g
Leave this space between WiFi antennas or use it for cellular antennas
6g           2/5g
2/5g         6g

.

Antenna Placement #3
--------------------
5g           6g
Leave this space between WiFi antennas or use it for cellular antennas
6g           6g
2/5g         2/5g

.

Antenna Placement #4
--------------------
       5g
6g           6g
Leave this space between WiFi antennas
Leave this space between WiFi antennas
2/5g        2/5g
       6g

Information about cable and antenna placement:

@VA1DER

Pigtails: I tend to use RG178. It is about the thickest cable that is feasible to use with U.FL connectors. I find it’s got the best loss characteristics while still being flexible enough to use. I recommend for each radio to use four cables the same length - this helps with beamforming. I keep a lot of 20cm cables since I find they are a good general purpose size for these types of cases.

@VA1DER

I asked myself also about antenna configuration. I mixed them 2 by 2. So on each side I have 2 antennas for 2.4 Ghz and 2 for 5GHz

This is a very reasonable orientation, and is great for a centrally located router.

Antenna configuration is actually a pretty complex topic. The answer depends very much on your home layout, how many walls and floors you need to penetrate, and on the very complex way in which multiple antennae shape a signal

In general a dipole radiates strongest in a plane 90 degrees from the direction it points (along the broadside of the antenna). Multiple dipoles tend to shape that signal more strongly in the direction 90 degrees from the direction the antennae are lined up (out from the “flat” of the two antennae). This is why truckers often had two CB antennae, one on either side of the cab on its mirrors, as they shaped the signal more strongly ahead and behind the truck. If your signal cables are different lengths, though, this will introduce e a phase change in the antennae that will induce deflection, and is the way phased arrays work. At 5GHz, which is a wavelength of about 5cm, it doesn’t take much difference in cable length to induce a significant phase shift and this will make your signal pattern very resistant to prediction.

My primary router, for ease of installation, is placed at the far end of my house on the second floor. So I placed all four 5GHz antennae on one side and shaped their flats to be more strongly radiating toward the house. I was less concerned about 2.4GHz since it has much better penetration, and found that I got sufficient coverage even with them being on the other side of the router. But I am sacrificing some 2.4GHz signal to improve my 5GHz throughout my house.

If your router is fairly central, then 2 & 2 is a great idea. Just don’t forget your upstairs and basement (if you have any).

@VA1DER

P.S i only have to cover one floor so no need for a certain angle. Jus keep em all straight Up, correct?

I’d likely rabbit-ear them a little, just to help the signal spread around objects, and to help with polarization.

A dipole puts out a signal polarized in the direction it points. Like polarized light. The antennae in devices tend not to be dipoles - they try and make them fairly omnidirectional, but that’s not possible in all instances (and given the flatness of phones and tablets). So if you have 100% vertical polarization in your router, but your device has an antenna that is more sensitive to a signal with horizontal polarization, then even given good signal strength you’ll lose signal. So rabbit ear them a little, or maybe lay one down, just to mix up the polarization in your footprint.

a 3d case model which has 4 left and 4 right, should we make 2g4 on one side and 5g on the other to have less interference or is mixing better as they operate on different base-band and so no interference happens?

For a centrally located router on a single-floor dwelling, with a 4+4 antenna placement on the case, I would recommend dipole antennae with the 5GHz placed in the corners and 2.4GHz placed in the middle on either side:

5g    5g
2g4  2g4
2g4  2g4
5g    5g

Even when they are not broadcasting together or on the same frequency, the physical placement of the other antennae will still shape the signal. In a 4+4 arrangement, you can expect each antenna to produce primary lobes that look something like this:

The first diagram shows the pattern coming out from the left and right antennae, and for clutter I omitted the signal coming the other way… The second diagram is showing the approximate signal pattern in both directions from the left antennae. These are both significant oversimplifications, and are based on all antenna being straight up. You can, for example, improve the right-hand radiation pattern of the left antennae by laying the top or bottom one down. So if you had 5g on one side and 2.4 on the other, I would likely lay the top antenna on the left side down and the bottom antenna on the right side down.

But for a centrally located router on a single floor dwelling, 5G in the corners and 2.4G in the middle will likely give the best general coverage.

@dangowrt

Instead of connecting all 2.4 GHz antennas on one side and all 5 GHz antennas on the other side you will get better results if you interleave them and thereby maximizing the distance between antennas which are used for the same band. 2~3 cm between two antennas of the same band will not allow for good results with MiMo, the more distance between them, the better…

[SpectreDev]

Btw if anyone reads this later, the 2nd one is available cheaper at digikey