A 14.6th-order 3.456GHz transmit baseband filter in 110nm CMOS for millimeter-wave communication systems

This paper presents a 1.728Gbps transmit baseband filter for transmitters of millimeter-wave communication systems. In order to avoid the inter symbol interference, ultra wide band and very high order filter is demanded. It is impracticable to realize such a high order filter with conventional analog technique, such as gm-C filter. The proposed filter consists of a 3.456GHz digital filter followed by an 8-bit 3.456Gsps digital to analog converter (DAC), which occupies 0.265mm
²
in 110nm CMOS processes. It is difficult to adjust the clock and data delay at 3.456GHz. The DAC has a clock divider for the high speed operation. The new filter consumes 142mW and achieves the transmit spectrum very close to the mask regulated by IEEE802.15.3c.