Phase-Aware Multitone Digital Signal Based Test for RF Receivers

Abstract

This paper presents a method for testing RF receivers that utilizes a multitone digital signal generation scheme and relies on the analysis of the receiver baseband output to compute the RF performance parameters. The proposed method eliminates the cost of expensive RF instrumentation on the input side of receiver testing and only requires low-cost on-chip baseband digitization at the output of the receiver. The complexity of the RF signal generation inherent to standard methods is traded off with extensive signal processing in the baseband. The analysis necessary for tackling the problem of extracting RF metrics is addressed and presented herein. Whereas the proposed test scheme was implemented and experimentally verified on a load board for testing UHF receivers, generalized use in BIST applications in need of multi-GHz RF stimuli is also discussed in the paper. RF performance parameters like Gain, Noise Figure (NF), and IIP3 were simulated and measured using both standard methods and the proposed method and, the results are shown to be accurate to within 0.5 dB for Gain and 1 dB for NF and IIP3.

A Regulated Pulse Current Driver with Spread Spectrum Clock Generator

“…In the following, we will introduce the parameter relationship of the periodic pulse signal demonstrated in the time domain and frequency domain, as shown in Figure 3a,b. Figure 3b is the corresponding spectrum with a well-known Sinc(x) shaping waveform superimposed on the tonal spectrum [11]. Thus, the frequency spectrum forms a Sinc function envelope, where the Sinc envelope peak can be expressed as Sinc envelope peak = 2f o W pulse (7) and the Sinc envelope nulls can be expressed as…”

Exploration of a digital-based solution for the generation of 2.4GHz OQPSK test stimuli

“…Although the ideal modulated RF signal has a constant amplitude, it is likely that the envelope of the generated signal exhibits some fluctuations, which are computed with: δ𝐴(𝑡) = 𝐴(𝑡) − 𝐴 𝑚𝑒𝑎𝑛 (10) To quantify the magnitude of the phase error and of the amplitude fluctuation, we will use the Normalized Root Mean Square (NRMS), which is respectively computed by: 𝑁𝑅𝑀𝑆-𝛿𝜑 = Finally, the last computation concerns the Error Vector Magnitude (EVM), which is the most widely used metric to express the modulation quality in wireless communication systems. Basically, it is a measure of the signal constellation deviation from its ideal reference.…”

“…Note that some works exist in the literature dealing with the generation of analog test stimuli from digital resources [6][7][8], but not applicable to test stimulus generation in the RF frequency range. An original approach for the excitation of RF devices is suggested in [9,10], which consists in using the harmonic tones of a pulse sequence. We intend to exploit this principle in order to generate a ZigBee test stimulus.…”