Evaluation techniques of frequency-dependent I/Q imbalances in wideband quadrature mixers

As bandwidths of digital wireless communications get wider, it is essential to evaluate the I/Q imbalances among quadrature mixer ports in terms of the mismatch characteristics of the analog components in the I and Q paths and the carrier phase offset. This paper describes a technique to evaluate frequency-dependent I/Q imbalances and carrier phase offset in wideband quadrature mixers. Using an SSB stimulus, the response of a DUT with imbalances is modeled mathematically, and an identification algorithm using a unique input stimulus is constructed. The validity of this technique is confirmed using an actual WiMAX transceiver on an ATE.

[1]  H. Kitayoshi,et al.  DSP Synthesized Signal Source for Analog Testing Stimulus and New Test Method , 1985, ITC.

[2]  Mikko Valkama,et al.  Pilot-Based Compensation of Frequency-Selective I/Q Imbalances in Direct-Conversion OFDM Transmitters , 2008, 2008 IEEE 68th Vehicular Technology Conference.

[3]  André Bourdoux,et al.  Pilot design for Joint Channel and Frequency-Dependent Transmit/Receive IQ Imbalance Estimation and Compensation in OFDM-Based Transceivers , 2007, 2007 IEEE International Conference on Communications.

[4]  A. Abidi.  Direct-conversion radio transceivers for digital communications , 1995, Proceedings ISSCC '95 - International Solid-State Circuits Conference.

[5]  Ali H. Sayed,et al.  On the baseband compensation of IQ imbalances in OFDM systems , 2004, 2004 IEEE International Conference on Acoustics, Speech, and Signal Processing.

[6]  Koji Asami,et al.  An algorithm to evaluate wide-band quadrature mixers , 2007, 2007 IEEE International Test Conference.

[7]  K. Soumyanath,et al.  A 1.4V, 2.4/5 GHz, 90nm CMOS system in a package transceiver for next generation WLAN , 2005, Digest of Technical Papers. 2005 Symposium on VLSI Circuits, 2005..

[8]  M. Moonen,et al.  Digital Compensation of RF Imperfections for Broadband Wireless Systems , 2007, 2007 14th IEEE Symposium on Communications and Vehicular Technology in the Benelux.

[9]  Sule Ozev,et al.  Low cost characterization of RF transceivers through IQ data analysis , 2007, 2007 IEEE International Test Conference.

[10]  Behzad Razavi,et al.  RF Microelectronics , 1997 .

[11]  Mikko Valkama,et al.  Compensation of frequency-selective I/Q imbalances in wideband receivers: models and algorithms , 2001, 2001 IEEE Third Workshop on Signal Processing Advances in Wireless Communications (SPAWC'01). Workshop Proceedings (Cat. No.01EX471).

[12]  Sule Ozev,et al.  Single-Measurement Diagnostic Test Method for Parametric Faults of I/Q Modulating RF Transceivers , 2008, 26th IEEE VLSI Test Symposium (vts 2008).