Software-Defined Front End Empowers Next-Gen Wireless Solutions
This article appeared in Microwaves & RF and has been published here with permission.
What you’ll learn:
- The need for wider bandwidths and more rapid processing and analysis of data in wireless systems.
- What does Apollo MxFE mixed-signal front-end platform bring to the table?
As wireless solutions become ubiquitous, the need for advanced RF infrastructures and systems becomes more pressing. The growth of advanced portable devices to address the needs of business, industry, and society in data-intensive applications is pushing demand for wider bandwidths and more rapid processing and analysis of data in wireless systems, especially at the network edge. Designers today need to accelerate design cycles and bring products to market faster and more cost-effectively, while future-proofing their product designs.
To address this demand, Analog Devices launched the Apollo MxFE, an advanced software-defined, direct RF-sampling, wideband mixed-signal front-end platform. The solution enables higher-speed data conversion and processing capabilities, while reducing electronic testing complexity. Apollo MxFE helps empower next-generation applications like phased-array radar, signals intelligence, industrial IoT, advanced test and measurement, aerospace & defense, and remote instrumentation.
Embracing issues like application versatility and rapid customization, the Apollo MxFE provides instantaneous bandwidths up to 10 GHz while directly sampling and synthesizing frequencies up to 18 GHz. The 16-nm CMOS device leverages high-dynamic-range RF analog-to-digital converter (ADC) and RF digital-to-analog converter (DAC) cores, and the company claims it has the best spurious-free dynamic range and noise spectral density available.
According to Bryan Goldstein, Vice President, Aerospace and Defense, at ADI, “The flexibility and simplicity designed into the Apollo MxFE platform has the potential to transform future engineering design for intelligent edge devices. Demand for higher data rates with shorter latencies at lower overall system power is accelerating across industries. Apollo MxFE gives design engineers the flexibility to design for those requirements today, as well as an ability to enhance performance over time using simple, software-defined design changes.”
Apollo MxFE Product Details
Presented as the industry’s first integrated radio capable of directly serving the emerging 6G frequency bands from 7 to 15 GHz, the Apollo MxFE 4T4R product has four 12-bit RF ADCs with a sample rate up to 20 Gsamples/s, four 16-bit RF DACs with a sample rate up to 28 Gsamples/s, an RF input bandwidth from dc to 18 GHz (Ku-band), and an instantaneous bandwidth up to 10 GHz. Features include on-chip DSP, a real-time FFT sniffer, a full-rate programmable FIR filter, a 128-tap complex FIR filter, fast-hopping NCOs, digital up/downconverters, and a fractional sample-rate converter (see figure).
The DSP is dynamically configurable to enable rapid changes between narrowband and wideband profiles without taking down the JESD link. The Apollo MxFE 8T8R offers eight RF ADCs with a sample rate up to 8 Gsamples/s, eight RF DACs with a sample rate up to 16 Gsamples/s, an RF input bandwidth up to 16 GHz, and an instantaneous bandwidth up to 3 GHz. The on-chip DSP offers similar features and functionality to the 4T4R device with double the number of digital blocks, which are all dynamically configurable.
Forming the core of a larger ecosystem of recently released ADI hardware and software products, Apollo MxFE is augmented by high-performance variable-gain amplifiers, ultra-low noise LDO and Silent Switcher regulators, clocking, and multichip synchronization. Its ecosystem includes subsystems like a PLL/VCO synthesizer with a fundamental frequency output of up to 22 GHz, offering noteworthy noise performance, temperature stability (0.06 ps/°C), and less than 1-ps alignment resolution.
The Apollo MxFE integrates the LTM4702 8A µModule regulator with Silent Switcher 3 technology to achieve high efficiency and excellent wideband noise performance. It also has a 10-channel precision synchronizer for time alignment of SYSREF signals to within 5 ps, for simultaneous sampling across multiple Apollo MxFE units on the same card or across different chassis.
On top of that, the Apollo MxFE can support two-dimensional system synchronization (fanout and/or daisy-chain architectures) for very large systems. Companion TxVGA and RxVGA solutions provide +15 dB of gain and the transition from single-ended to differential on Rx as well as differential to single-ended on Tx, to simplify the connection to the RF front end.
