A 60 GHz 256 QAM balanced vector modulator for short range LOS communication applications

A novel broadband MMIC vector modulator for V-band applications

“…demonstrates an IL lower than 10.6 dB at the frequency of 40 GHz. The VM proposed and realized by Nam et al [10] exhibits a 5 dB IL and a return loss lower than 10 dB, but over a smaller frequency range, from 55 to 65 GHz. Further, the VM realized by McPherson et al [16] demonstrates 10 dB IL at 66.5 GHz and a return loss lower than 6 dB.…”

“…To solve the problem, two main strategies are possible: the first one, reported in [18], is based on direct parasitics compensation, being therefore suitable for narrowband applications only; the second one is the balancing technique, mostly used for broadband applications [9][10][11][12][13][14][15][16][17].…”

“…The resulting BM die, 1.8 Â 1 mm 2 in size, has been designed to operate from 45 to 65 GHz band; a microphotograph is depicted in Figure 11. Other VMs have been designed to operate in this band such as [9] and [10]. The band around 60 GHz has been selected since, due to a high atmospheric absorption, it is suitable for short-range radio communication applications.…”

“…In particular, four 90 deg couplers (Lange Couplers) are typically adopted, leading to an overall number of nine couplers for a complete VM scheme, composed by two BMs. Despite some realizations have been presented, also in monolithic form [9][10][11][12][13][14][15][16][17], a different implementation approach is highly desirable, leading to an improvement in circuit size and sensitivity. In this article, a novel VM topology is presented, based on the combination of two BMs, whose operating mechanism is based on the balanced load principle.…”