The mobile communication system is mainly composed of mobile station (MS), base station subsystem (BS) and network subsystem. The BS consists of the base station transceiver station (BTS) and the base station controller (Base Station Controller), BSC in the operator's room, Cloud Tranceiver the two BTS is the tower we see.
A complete BTS includes a wireless transmit / receive device, an antenna, and a signal processing section specific to all wireless interfaces. BTS can be seen as a wireless modem, Cloud Tranceiver responsible for the mobile signal reception and transmission processing. In general, in a certain area, a number of sub-base stations and transceivers to form a cellular network, by controlling the transceiver and the transceiver between the signal transmission and reception, Cloud Tranceiver to achieve the transmission of mobile communication signals.
Wireless systems are everywhere, and the number of wireless devices and services continues to grow. Design a complete RF system is an interdisciplinary design challenge, Cloud Tranceiver analog RF front end is one of the most critical part. However, the introduction of integrated RF transceivers such as the AD9361 significantly reduces RF challenges for such designs. These transceivers provide a digital interface for analog RF signal chains, allowing easy integration into ASICs or FPGAs for baseband processing. Cloud Tranceiver The baseband processor (BBP) allows user data to be processed in the digital domain between the terminal application and the transceiver device. In addition, Cloud Tranceiver the use of Simulink and other system modeling tools can easily complete the baseband processor design.
Data requires timing information, bit spacing. Cloud Tranceiver The maximum possible bit interval is the sampling period. In order to keep the receiver simple, it takes enough time to decode the signal and make a decision. The simplest timing recovery method is zero crossing and peak detection. In this case, the peaks will be inconsistent. Therefore, select the zero crossing for bit interval detection and tracking. Cloud Tranceiver There are also carrier differences between the two systems. In some cases, Cloud Tranceiver at any point in the user's data, the sample may be blurred. Four samples are set for every half sinusoidal signal, and the interval is set to 8 samples.
Since the systems are not synchronized with each other, the receiver's signal will have amplitude, Cloud Tranceiver frequency, and phase errors. The demodulated signal is a signal that changes the phase of the transmitted signal relative to the local carrier. The carrier may be tracked for some time, Cloud Tranceiver select the data, and then track it. Therefore, the design needs to be prepared for partial data loss. Cloud Tranceiver To this end, the data is transmitted as a packet. Can repeatedly transmit multiple packets, rather than the entire data.