Patent · US Expired

Versatile baseband signal input current splitter

US7643847B2 · kind B2 · utility

23Cited by
6References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 9, 2004
Grant dateJan 5, 2010
Priority date
Expiry dateMar 31, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/406
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A current steering mechanism is provided in a radio transmitter (e.g., a multiband radio transmitter) to provide compatibility with a variety of baseband parts. Different proportions of an input signal current (“in”) may be steered to a dummy load (103), a mixer for a first band (106), and a mixer for a second band (108). In one example, five different loads are provided, one dummy load (103) and two different loads (105, 107) for each band. Possibilities include: 1. All current steered into dummy load via transistor A; 2. All current steered into Band 1 mixer via transistor B; 3. All current steered into a Band 1 mixer via transistor C, causing 6 dB input signal amplification; 4. All current steered into Band 2 mixer via transistor E; 5. All current steered into a Band 2 mixer via transistor D, causing 6 dB input signal amplification; 6. Like cases 2-5 but with diversion of some portion of current via a dummy load for attenuation of input signal in 1 dB steps.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.