Sat Radio cuts out does it have any memory

I've had the same issue.
As a relatively new buyer I just filled out my Toyota evaluation form and gave glowing reviews on pretty much everything but the SAT and sound quality.

 

Do they have memory? Memory would mean the audio is delayed from real time. Its most likely a lack of signal sensitivity. Some designs are better than others.

 

I believe the problem is lower power from the satellite. On the way to the gym there were lots of "cut outs" which never happens, no trees or other problems. On the way home there were a lot fewer cut outs. It would make sense that the antenna has some directional sensitivity variations which would show up with low satellite power out. Different manufacturers cars could still have different results with different designs.

 

I think you mean streaming buffer? I guess apparently not as mines does the same. I would also think SAT radio sound quality would be better. FM HD radio sounds a little better if I remember right(subscription expired).

 

You are right, there is a reasonably large streaming buffer that may be different with different radios. So the recent drop out problem seems to be low power output such that the buffer and error correction can't keep up with the program.

 

Satellite radio can't have a streaming buffer, because it simply wouldn't work. In order for a streaming buffer to work, there has to be two-way communication for the receiver to tell the transmitter that data has been lost so the transmitter can resend lost data. Satellite radio is one-way, so there is no way for the receiver to tell the transmitter about lost data, hence no streaming buffer.

 

You're right, its not like file transfer where the receiver can tell the transmitter to resend some data.

The buffer has to do with error correction. You can't correct the errors until you have all the data that is "protected" by the available correction data. That requires a "streaming" buffer. While the transmission of the audio and error correction data is to a Standard, receivers can have different implementations of the correction, some more powerful than others. And, in the case of low power due to transmitter problems or trees, receivers can have different sensitivities hence a different amount of errors to correct.

 

From Wiki, from what I read here, it should have about a 4 second buffer.
"
Technology[edit]

The Sirius signal is separated into three carriers, one each for the two satellites, and the third for the terrestrial repeater network where available. Sirius receivers decode all three 4 MHz carrier signals at once to achieve signal diversity. This is in contrast to XM which uses six carriers and decodes three 2 MHz carriers to economize on receiver power consumption and complexity at the cost of channel-changing speed. There is an intentional four-second delay between the two satellite carrier signals. This enables the receiver to maintain a large buffer of the audio stream, which, along with forward error correction, helps keep the audio playing in the event that the signal is temporarily lost, such as when driving under an overpass or otherwise losing line-of-sight of any of the satellites or ground repeater stations.
A third, separate signal is uplinked to the AMC-6 Ku-band satellite and received by 36-inch (910 mm) satellite dishes for the ground repeater network. This third signal is broadcast on a third segment of the signal."

 

It appears to depend on channels. 69 lots of drop outs, 71 not so much.

 

I would say no. My sirus portable kept about 90 mins worth of songs in a buffer. I would pause my radio and come back and forward past songs I did not want to hear. I never lost a signal. This SAT radio will lose a signal all the time if trees are around. I may cancel my subscription.

SCH-I535 ? 2

 

Consider simply replacing the satellite antenna.
That's what I did as a cheap ($20) "try-n-see" fix....and it worked!
See the following thread:
Improving XM Satellite Radio Reception | PriusChat

 

My Prius does the samething. If you google it, it is a common problem.
The antenna is located in the wrong location. This is what I found out. It is sad that a 28K car has this problem.

SCH-I535 ? 2

 

The location seems to be pretty much the same as on most cars. It must be other factors like antenna design (which is different than most) or receiver sensitivity. I only have problems in the mountains/forest.

 

I also find my sat radio connection spotty compared to the one that came in my Hyundai Sonata. That one almost never cuts out on me. I lose connection going under an overpass for example. I'm not an expert in the technology but since the PiP satellite radio works perfectly fine parked backwards into my garage, I wonder if it's a buffering problem and not a signal problem.

 

Yep trees everytime!

SCH-I535 ? 2

 

There are 2 things here, both of which have already been touched on. They use multiple satellite streams with an offset time base so that at any given time you are receiving the audio for t and t+4 seconds. If you decode them separately and played them on 2 different speakers, you would hear the same thing on the 2nd speaker as the 1st speaker, just delayed by 4 seconds. This is on all channels, it is literally just a time shifted signal equal to the original.

The receiver then can choose to implement or not implement a buffer. If you store 4 seconds of buffer, then when you lose signal, you have exactly 4 seconds that you will continue playing audio that is has stored from the t+4 audio stream. If exactly 4 seconds later you regain satellite reception, it can now play the t+0 stream and it is like nothing happened while the buffer refills with the t+4 stream. But if you lose reception 1 second later, you only have 1 second of future looking t+4 stream. So now you only have audio for 1 second without reception. In dense areas or areas with poor reception (trees/skyscrapers) your signal may be cutting out every couple of seconds but the buffer is able to keep up because of the simultaneous streams so you never see a difference. Only right after marginally working do you get poorly working to not working. In these cases it is almost always really heavily treed areas or skyscrapers. The solution is to use a 3rd receiver on a much larger wavelength, the ground based repeater stations. These work like your local radio station essentially and when it can`t see the sky, it can pick up these high power, low frequency waves that travel pretty far and without obstructions.

Now there are other radio`s, most notably the addons, that have a built in flash buffer that can store 90minutes or more of music. This is nothing more than recording what it receives for a long time. If your receiver has audible cutouts, then your recording will also have audible cutouts, although generally there is nothing so you just get a discontinuous jump not a brief silence as if you were listening in real time.

The other solution is the internet streaming. They actually do have independent and individual streams of data for every user endpoint. You can pause music, rewind, fast forwards, anything and your station will be unique to you. A small buffer is stored on your mobile device, but it is used to buffer the internet stream. If it disconnects, it will pick up where it left off, you will not have an audible gap. It is a pretty cool feature. And of course you can play it on your smartphone and plug it into the car.

As to why yours is cutting in and out, my guess is poor reception. I use an external model plugged into the aux port because it gives me 90s of buffer. Sometimes I want to rewind and playback a good song, or skip ahead over some crap that pops up now and then. But I also listen about half the time on my phone through the bluetooth audio playing sirius music or streaming the BBC live. Interestingly a lot of channels that were on Sirius pre-XM merger are still available online, but not through satellite reception. For instance you can listen to the BBC Radio 1 stream timeshifted by 5 hours online and through the internet apps with Sirius` online. But you can`t tune to it with the vehicle receiver.