Helios™ II EDGE RF Subsystem
Complete
two-chip, Helios EDGE-based subsystem for quad-band (GSM850,
EGSM900, DCS1800, PCS1900) cellular handsets
Skyworks Helios II EDGE RF Subsystem combines a direct conversion transceiver, PA, and a PA controller/modulator into a dual-chip radio solution that saves significant space, cost, and design cycle time while providing world-class GSM/GPRS/EDGE performance.
At the heart of the radio subsystem is Skyworks advanced Polar Loop™ transmit modulation architecture, which enables the radio to transmit both constant and non-constant envelope signals through the same transmit path to minimize the number of external components required to build a mobile handset. This significantly reduces the complexity, size, cost, and power requirements of next-generation EDGE platforms.
The Helios II EDGE RF Subsystem features:
- Polar Loop transmit modulation architecture
- Four integrated differential LNAs
- Integrated noise filtering; no pre-PA filters required
- Closed loop phase and amplitude modulation (GMSK,π/8 8-PSK) via control of non-linear GSM PA
- PA inside control loop provides excellent EVM and phase error performance with up to 6:1 VSWR without external isolator
- Transmitter with integrated VCOs
- Fully integrated fractional-N synthesizer and UHF VCO
- Impedance matching circuitry
The Helios II EDGE RF Subsystem consists of:
- SKY74137 RF Transceiver – Direct conversion transceiver eliminates the need for special baseband processing interfaces. The device also includes Skyworks Polar Loop™ transmit modulation architecture.
- SKY77331 Power Amplifier With Integrated Coupler – A highly integrated PA and PAC with separate GSM850/EGSM900 and DCS1800/PCS1900 control blocks, envelope amplitude control, 50 Ohm I/O matching circuitry, and excellent EVM and phase error performance.