Indy R1000 Datasheet - Impinj

Indy R1000 ® Electrical, Mechanical, & Thermal Specification
5.3.2 Power Scaling
The power scaling block is a multiplier in which the input is multiplied with a programmable value. The gain of the I and the Q channels can be
programmed independently.
5.3.3 Hilbert Transformer
The Hilbert transformer is used to generate a SSB signal from a DSB AM signal. The coefficients are anti-symmetric, and every second coefficient is
zero (the first being non-zero). All non-zero coefficients are programmable. The order of the filter can be programmed to two discrete values: 22 and
10. When the 10th order Hilbert transformer is used, all coefficients that are not used must be programmed to zero. The 10th order Hilbert filter is
used to avoid ISI in the modulated data.
5.3.4 Frequency Shifter
The frequency shifter is used for shifting the spectrum in SSB mode so that it is centered in the middle of the channel. It is also used for shifting the
LO in listen before talk (LBT). The frequency shifter is based on the CORDIC algorithm.
5.3.5 AM Pre-distortion
AM pre-distortion uses a fifth order polynomial work function. This equation defines the function, where x is the input and y is the output of the
block.
Y = C 0 + C 1.X + C 2.X 2 + C 3.X 3 + C 4.X 4 + C 5.X 5
The coefficients C 0 through C 5 are programmable. This function is used during DSK-ASK polar modulation.
5.3.6 Upsampling
For low data rates, the baseband signal needs to be upsampled and filtered prior to the oversampling of the DAC. This process suppresses the images
at multiples of the original sample rate. For modes with a high sample rate or when spectral purity is of lesser concern, the upsampling can be
bypassed.
The upsampling uses a standard upsample and filter approach. The filter is a 17th order FIR filter with fixed coefficients.
5.3.7 Sigma Delta Digital to Analog Converter
The conversion from digital to analog is performed by a third order sigma-delta DAC. The structure of this DAC is illustrated in Figure 8, and the
specification values are provided in Table 16.
20 Revision 2.3, Copyright © 2012, Impinj, Inc.