GSM Frame Error Rate (FER) Testing: 900MHz & 1800MHz Limits

FER stands for Frame Error Rate. When performing FER TCH (Traffic Channel) testing on a GSM UE (User Equipment, i.e., a mobile phone), it’s crucial to verify that it meets the specifications for various frequency bands, including GSM850, GSM900, DCS1800, and PCS1900.

The 3GPP standard TA document 51.010, specifically test case section 14.5.1.2, defines the limits for this test. These limits apply to various physical channels, such as:

• FACCH (Fast Associated Control Channel)
• SDCCH (Standalone Dedicated Control Channel)
• RACH (Random Access Channel)
• SCH (Synchronization Channel)
• TCH-FS (Full Rate Speech Channel)
• TCH-HS (Half Rate Speech Channel)
• TCH-EFS (Enhanced Full Rate Speech Channel)

These limits are specified at the reference sensitivity level, determined according to the mobile subscriber class.

GSM 900 Band Specification Limit

Here’s the limit table for the GSM 900 band:

Where $1 \le \alpha \le 1.6$. The value of $\alpha$ can vary for each channel condition.

DCS1800 Band Specification Limit

The following table details the specification limits for the DCS1800 band:

Reference Receiver Sensitivity Level

• DCS 1800 band: For Class 1 or Class 2 MS, the level is -100 / -102 dBm.
• GSM 900 band: For small Mobile Subscribers (MS), the level is -102 dBm.

This information is critical for proper testing and ensuring GSM UE performance within specified parameters.