Globalsat BT-328 Review
1. Introduction
Globalsat BT-328 - Page 1
- Introduction
After the release of the now infamous BT-338 based on the SiRF III chipset , Globalsat  recently announced a new GPS device, the BT-328, this time powered by another SiRF chipset, the GSC2. A general  overview and its performance are presented in this review, where we compare it with, none other than the BT-338. Do we have a new winner in the GPS race? 
- Globalsat BT-328
The BT-328 is the latest Bluetooth GPS from Globalsat, built on the latest SiRF GSC2 low power technology. It combines performance with low cost, creating an entry level BT GPS at a very attractive price. Compatible with any device offering a Bluetooth compliant serial interface, it can provide accurate GPS position information for up to 16 hours continuously.
 
- Features
• New SiRF GSC2 high performance and low power consumption chipset
• Communications with Host Platform via Bluetooth Serial Profile
• Built-in ceramic patch antenna 
• Supports NMEA0183 data protocol
• 3 LEDs to show the status of GPS/Bluetooth/Battery
• Rechargeable Li-ion battery
• Operation time: 16 hours, in continuous mode
• Auto power-off, if Bluetooth is not connected to any devices within 10 minutes
• Bluetooth operation range: 10 m 
- Used chipset
The SiRF GSC2 chipset has the following specifications:
Chipset:   | 
    SiRF GSC2  | 
  
Frequency:  | 
    1,   1575.42 MHz  | 
  
C/A code:  | 
    1.023   MHz chip rate   | 
  
Channels:   | 
    12   channel all-in-view tracking   | 
  
Tracking Sensitivity:   | 
    -155 dBm   | 
  
Position Accuracy:  | 
    10   meters, 2D RMS    | 
  
Velocity:  | 
    0.1   m/s  | 
  
Time:  | 
    us synchronized to   GPS time   | 
  
Default:  | 
    WGS-84   Acquisition Time (Open sky, stationary)  | 
  
Reacquisition:  | 
    0.1   sec., average   | 
  
Hot start:   | 
    8 sec.,   average   | 
  
Warm start:  | 
    38   sec., average   | 
  
Cold start:  | 
    42 sec., average   | 
  
Altitude:   | 
    18,000   metres (60,000 feet) max.   | 
  
Velocity:   | 
    515   metres/second (1000 knots) max.   | 
  
Acceleration:  | 
    Less   than 4g  | 
  
Jerk:  | 
    20 m/sec  | 
  
Protocol messages:  | 
    NMEA 0183 protocol  | 
  
Output format:   | 
    Supports command: GGA, GSA, GSV, RMC, VTG, GLL (VTG and GLL are optional)  | 
  
Operating   temperature:  | 
    -20° to 60°   C  | 
  
Humidity:  | 
    5% to   95% Non-condensing  | 
  
Looking at the SiRF GSC2 specs and compared with the SiRF III, we notice the following:
- SiRF GSC2 chipset doesn't support WASS/EGNOS
 - SiRF GSC2 chipset supports 12 channels whereas the SiRF III 20 channels all in view
 - SiRF GSC2 chipset hot start time is 8secs whereas the SiRF III is 1 sec
 - BT-328 has 16 hours whereas the BT-338 17 hours operation time
 - BT-328 is smaller (thinner) than the BT-328 and lighter in weight