Is the Death of Internet Radio Imminent?
There are three principal frequency bands within which the latest wireless loudspeakers work in: 900 MHz, 2.4 GHz and 5.8 GHz. The increasing competition within the frequency band has forced designers to come up with new methods to deal with the greater levels of interference. One of which I’m going to explain in this article.
The adaptive frequency hopping technique is one of the most sophisticated methods which works by searching the entire frequency spectrum for channels that are occupied by different transmitters. The frequency channels that are not occupied are marked as being vacant. In addition to the vacant channels there is a hop set defined as an assortment of frequencies that are not occupied. In the course of a cordless transmission the transmitter utilizes one of the available frequencies for a short time frame, typically up to 10 milliseconds. Then , it shifts to the next frequency channel in the hopset. When the frequency channel is changed to another channel, both receiver and transmitter change to the next channel. This makes sure that both transmitters as well and receiver transmit on the exact frequency. This is why the hop set must be sent to each receiver.
If a different wireless device begins to occupy a channel, which is one of the frequencies that are in use The hop set must be changed. In such a situation the transmitter scans every channel continuously and keeps a list of channels that are free. If the active channel is filled and the transmitter removes that channel from the active hop set, and then selects one of the free channels that are part of the new hop set. The alternative channels allows that the set of hops to be modified quickly and this technique is highly efficient in avoiding interference, and also limiting broadcasting to channels that are already occupied.
Other methods are commonly used on top of adaptive frequency hop. These techniques also increase the reliability of wireless music transmission. Data buffering is a commonly used method. Data buffering was developed to protect against damage or loss of packets due to inadequate reception or possibly 메이저놀이터. The information packets delivered are identified with numbers. A checksum (often called CRC) is added to every packet. When the packet is transmitted, the transmitter saves recent information packets in their internal buffer. If a particular packet ended getting damaged or lost the receiver will to request the transmitter to retransmit the damaged or lost packet. This kind of feature calls for a backup channel, and also time slots where each receiver is able to ask for packets from transmitters and this feature supports a restricted number of wireless receivers each transmitter.