Efficient SDR baseband processing - an essential step in the car smart touch screen

Software-defined radio (SDR) performs baseband processing through software and supports a wide range of radio standards using the same radio platform. This method is essential for in-vehicle intelligent multimedia touch screen systems. In contrast, conventional radio receivers require the number of radio receiver chips to be the same as the number of supported radio standards.

The SDR method can be used to implement all signal processing after an analog to digital converter (ADC). To simplify design and support greater efficiency, some features can be implemented in front-end hardware. To simplify the interface, downsampling can be implemented in the front end to reduce the bandwidth of the interface between the front-end device and the SDR processor. Any signal processing implemented in the front end must be sufficiently adaptable to avoid compromising the flexibility of the SDR backend. In an ideal SDR implementation, any signal processing associated with a particular standard should be implemented using SDR technology, so that the same radio front end can support a wide variety of broadcast standards through SDR software.

Figure 1. Functional block diagram of the MAX2175

Although baseband signal processing can be implemented in software via SDR, the software still needs to run on the hardware platform. One potential approach is that the same chip can have two baseband signal processing cores, each with its own front end to handle AM ​​and FM signals. However, since the number of standards is not limited to this, this type of architecture does not fully support the SDR strategy. To fully realize the original SDR, you need a more flexible architecture. Maxim has proposed a full-band radio (WBR), a stand-alone front-end tuner that implements all major analog and digital radio standards. The tuner works with the SDR backend, allowing the same radio platform to support all radio standards worldwide.

For more information on how WBR can help you realize the full potential of SDR, please refer to our design: "Select a flexible, scalable front-end tuner for software radios." You'll learn more about the system partitioning steps required for software-controlled baseband signal processing and more information on how the MAX2175 RF-to-bitstream car wireless tuner supports flexible, scalable SDR implementations.