That’s pretty interesting. Lots of information but not a straight answer. Proprietary comes to mind. Looks like the license allows a frequency and wattage.
It uses bluetooth.
BLE is generally proprietary, because there aren’t as many profiles for it as there are for BTC. Consider BLE as a toolkit that you must customize to use, rather than a finished product. Maybe some day that will change.
This is from a google search. The frequency range does jive with the TV Connector. It also mentions different type Bluetooths. Phonaks device could be any of them.
Bluetooth devices intended for use in short-range personal area networks operate from 2.4 to 2.4835 GHz. To reduce interference with other protocols that use the 2.45 GHz band, the Bluetooth protocol divides the band into 80 channels (numbered from 0 to 79, each 1 MHz wide) and changes channels up to 1600 times per second. Newer Bluetooth versions also feature Adaptive Frequency Hopping which attempts to detect existing signals in the ISM band, such as Wi-Fi channels, and avoid them by negotiating a channel map between the communicating Bluetooth devices.
The USB 3.0 computer cable standard has been proven to generate significant amounts of electromagnetic interference that can interfere with any Bluetooth devices a user has connected to the same computer.[1] Various strategies can be applied to resolve the problem, ranging from simple solutions such as increasing the distance of USB 3.0 devices from any Bluetooth devices to purchasing better shielded USB cables.[2]
OK, thank you. It would have been more helpful to circle the Bluetooth symbol which I was unfamiliar with. The frequency range is the same as Roger.
On another note, I feel my Marvel 90-13T’s have better Bluetooth range following the Marvel 2.0 update. Left my phone downstairs streaming music, walked upstairs and into a room and it was still going strong.
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Oh, please. A Bluetooth symbol in the Frequency Range Operating Frequency column means it uses Bluetooth frequencies. It doesn’t mean it uses Bluetooth or BLE protocols. BLE is nearly mathematically impossible, and Bluetooth is highly improbable given the Independence of the earpieces.
There’s a possibility that it may actually use the same radio chip that Bluetooth and BLE use. There are many devices that do this – they use the same physical-layer transport (radio chip) and fan out the data stream in software into different interpreters for the different protocols. But every indication, except frequency range (which is completely generic), is that it does NOT use either Bluetooth or BLE protocols.
As I said in an earlier post that my startup used a time-division (as opposed to frequency-hopping) protocol using a WiFi radio chip (same as Bluetooth radio chip) to implement a hi-fi stereo true one-to-many digital music transmission. This is IMO the most likely implementation type for AirStream. Something completely outside Bluetooth protocols to avoid pairing problems and achieve true one-to-many operation.
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You just can’t stand to be proven wrong. The FCC doesn’t plaster a Bluetooth symbol on just anything in those frequencies, LOL. Let’s be real here. It uses Bluetooth LE.
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It does when it’s a “Frequency Range” topic.
I live and breath these protocols. It’s impossible for it to be BLE. And the way it operates is really different from Bluetooth operation.
Regarding BLE usage, read the paper below.
" The lower the connection interval, the higher the potential data rate is. E.g. using the smallest connection interval of 7.5 ms e.g. with 125-byte useful payload / connection interval, the radio can (assuming no lost packets and no re-transmissions) achieve a theoretical data rate of:
1000 ms / (2 * 7.5 ms) * 125 bytes = 8,333 bytes/sec = 66,666 bps"
Translated: you can’t send stereo hifi audio even within an 8K bandwidth (for which you need at least 16K sampling rate for Nyquist anti-aliasing). You’re an order of magnitude off. Even if you accept very lossy data.
These are the only people who are doing hi-fi audio over BLE. They probably use compression up the wazoo because BLE bandwidths are so far off of hi-fi audio. But Dialog does it with a proprietary chip. And it’s at proof-of-concept stage, not something that Phonak has.
Hi-fi audio protocols on 2.4GHz using other protocols are easy and prevalent. Existing BLE can’t do it. Regular Bluetooth wouldn’t work the way the TV streamer does. Ergo it’s far more likely to be a different protocol than for Phonak to have proprietarily developed a hi-fi compression over proprietary BLE years ago when Dialogic is just announcing it now as a proof-of-concept.
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If the device was radiating in the BT range but not using BT, the BT logo would not be present. It would just specify the frequency range.
According to the link below, Phonak is using a very powerful BT SOC. I haven’t seen one bit of evidence that Phonak (or the other manufacturers) are using proprietary RF technology other than BT for streaming.
No offence, but what you’re claiming BLE is capable of doing seems to be inconsistent with what it’s being used for. BLE is used for both Apple MFi and Android ASHA, both of which go significantly beyond what has been done previously with BLE in terms of streaming bandwidth.
HAs are not hi-fi. The frequency range is not very high.
Daryl, all of what you say in the last two posts is true. I don’t dispute any of it.
What I don’t believe is that you can send TV audio in the bandwidth I can sense over BLE without an order of magnitude more frequency range. Do the math.
The audio doesn’t have to be 44KHz CD quality to be “hi-fi”. From what I hear through my TV connector, the audio is at least 16 bits and at least 8KHz. Nyquist sampling frequency would have to be 16 KHz minimum. As I have said, I have a TV Connector and I’ve done enough audio engineering to know this frequency range is actually conservative. I can also tell it’s stereo.
You need 32 KBytes/sec to transmit that data and BLE has less than 8KBytes/sec if you stretch it and disable retransmissions.
The TV connector drops out in either ear, and we know the right HA is the only one that makes BT Audio connections, so it’s not A2DP BT.
The Sonova chip says “The integration of CEVA’s advanced Bluetooth Dual Mode IP into our wireless chip enables us to bring low power stereo audio streaming and data connectivity to our hearing aids…” which means Standard BT A2DP and HFP for stereo audio streaming and phone calls, and BLE for data connectivity for power level and program selection.
(EDIT) Sorry I didn’t realize that the Sonova chip was relaitve to the TV Connector directly. Some of that last paragraph doesn’t apply to the TV connector. (EDIT)
Neither BT Profiles nor BLE GATT profiles can perform one-to-many streaming.
Sonova also says they support client IP which would support a custom 2.4GHz protocol over Bluetooth physical-layer transport for true one-to-many receivers for TV Connector streaming.
So a Bluetooth symbol on a frequency range and a vague word-association with a multi-protocol chip does not imply that the TV Connector uses any of the available Bluetooth profiles when it flies in the face of all the information and empirical evidence. All the information except for a single graphic symbol taken out of context.
Haven’t read up on MFI, but Android ASHA has the basic bandwidth “at the expense of latency” (which I do not experience with TV Connector), but is CoC-based (“Connection Oriented Channel”), like a point-to-point TCP/IP socket. It does not support one-to-many broadcast transmission that the TV Connector supports.
In engineering we consider all the details. I just can’t draw conclusions from abstractions. I could still be mistaken, but all the evidence I’ve seen is to the contrary about the TV Connector and BLE.
And regarding the BT Symbol, show me where it says use of that symbol requires that the FCC Cert is for a strict BT profile or BLE GATT profile and those profiles only. FCC certs are for radiation levels, bandwidth occupation (in the case of frequency-hopping), and sideband emissions (part of radiation levels). They don’t certify or care about protocols.
I concede that the TV connector could use BLE GATT profiles for signalling. Perhaps this is what the Bluetooth symbol is for. But not for audio with one-to-many capability.
Thanks for your reply. In the reference about ASHA, there is the following:
It is strongly recommended that the central and peripheral support 2MB PHY as specified in the BT 5.0 specification. The central shall support audio links of at least 64 kbit/s on both 1M and 2M PHYs. The BLE long range PHY shall not be used.
Is that the bandwidth you are looking for?
Using the right (or left. as configured) is only because HFP and A2DP by definition do not support multiple connections. However, BTC is not used for TV streaming, MFi or ASHA. With my Opns, MFi works with either one or both HAs. Similarly the ConnectClip. Similarly the TV box. So in all cases, presumably specialized BLE / GATT profiles must be being used.
Regarding one to many, according to GATT | Introduction to Bluetooth Low Energy | Adafruit Learning System, one central device may be connected to multiple peripheral devices.
@haggis @darylm Sorry if I missed it earlier in your discussion but the subject of passing an FCC certification to get a BT logo seems to have come up a time or two. All I know about it is that I just looked it up at bluetooth.com but it appears from the following that the BT symbol/logo is a TRADEMARK and it is issued by the BT SIG and is only assigned on two bases (plural of basis): 1) the company involved is a BT SIG member, and 2) the product is certified by the BT SIG as qualifying for its designation.
https://www.bluetooth.com/develop-with-bluetooth/marketing-branding/
Streaming audio cuts out from both ears when the left stops talking to the right. From this article:
“The fundamental drawback of their approach is that they rely on a 2.4 GHz signal to transfer information between the hearing aids. The technical characteristics of the signal means that it is inefficient to transmit the signal in a straight line between both ears. Instead, the 2.4 GHz signal relies on reflections from walls and other hard surfaces when it’s transmitted from one hearing aid and received by the hearing aid on the opposite ear… Provided there are hard surfaces in the wearer’s immediate vicinity then the signals are transmitted successfully between the ears and the wearer enjoys a continuous high-quality streamed signal. The problem arises when there are no hard surfaces such as walls and ceilings to facilitate transmission between the ears, such as in large halls or outdoor spaces.”
More on this topic here:
–rex
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@haggis Take a look at this: SBO Hearing A/S TV Adapter TVA3 FCC ID 2ACAHTVA3, which is the FCC page for the Oticon TV Adapter. It appears the product was initially released using BT LE @ 1 Mbps / 4 mW, using GFSK, then revised to use FHSS @ 2 Mbps / 21 mW, using 2GFSK. It appears like it’s a modification of BT LE to get more BW, but using quite a bit higher power. (The first test report is for the BT LE version. The second test report is for the FHSS version.)