This part is a kind of semiconductor called RF7188.

Function of this product has DUAL-BAND GSM900/DCS1800 TRANSMIT MODULE.

Manufacturers : RFMD

Image and pinout :

Some of the text within the PDF file :

RF7188 DUAL-BAND GSM900/DCS1800 TRANSMIT MODULE Package Style: Module (6mmx5.93mmx1mm) GND VBATT VBATT GND GND GND Features  High Power and High Efficiency Transmit Module  GSM900 PAE 34%  DCS1800 PAE 38%  GSM900 POUT 33.4dBm  DCS1800 POUT 31.9dBm  Less Current Consumption at Rated and ECTEL Power Levels  Integrated Power Flattening Cir- cuit for Lower Power Variation under Mismatch Conditions  Integrated VBATT Tracking Circuit for Improved Switching Spectrum under Low VBATT Conditions  Dedicated RX Ports  Excellent ESD Protection at Antenna Port: 8kV Applications  GSM900/DCS1800 Products  GPRS Class 12 Compatible  3V Dual-Band GSM/GPRS Handsets  Portable Battery-Powered Equipment GND 22 15 GND 21 20 19 18 17 16 NC TXIN_LB TXIN_HB GND TXP VP [ ... ]

RF7188 PDF Datasheet Download