Estimation of radio channel bit error rate in a digital radio telecommunication network

• US 5,828,672 A
• Filed: 04/30/1997
• Issued: 10/27/1998
• Est. Priority Date: 04/30/1997
• Status: Expired due to Term

• Current Assignee: Telefonaktienbolaget L.M. Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Turcotte, Eric, Labonte, Sylvain
• Primary Examiner(s): Chung, Phung M.
• Application Number:
  US08/846,630
• Time in Patent Office: 545 Days
• Field of Search: 371/5.5, 371/5.1, 371/28, 370/333, 370/252
• US Class Current: 714/708
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/203 Details of error rate determination, e.g. BER, FER or WER
• CPC Class Codes: H04L 1/208 involving signal re-encoding

Abstract

A system for determining when a radio telecommunications network should switch between a first grade of service and a second grade of service based upon a highly accurate and reliable estimate of the bit error rate (BER). The system estimates the BER on an uplink and a downlink on a user channel, and determines whether the BER on the uplink and the downlink on the user channel are below a first set of thresholds. The system then measures the residual BER (RBER) and the frame erasure rate (FER) on the voice channel uplink, and determines whether the downlink BER, the uplink RBER, and the uplink FER are lower than a second set of thresholds. If lower, the system sends and receives a data message on a Fast Associated Control Channel (FACCH). The system obtains a highly accurate estimate of the BER on a downlink on the FACCH channel, and reports the downlink BER in a message on the FACCH channel uplink. The system then estimates the BER on the FACCH channel uplink. Finally, the system switches the radio telecommunications network from the first grade of service to the second grade of service in response to determining that the uplink and downlink BER on the FACCH channel are below a third set of thresholds.

Claims

1. A system for determining when a radio telecommunications network should switch between a first grade of service and a second grade of service based upon a highly accurate and reliable estimate of the bit error rate (BER), said system comprising:

means for estimating the BER on an uplink and a downlink on a user channel;

means for determining whether the BER on the uplink and the downlink on the user channel are below a first threshold;

means for sending and receiving a data message on a Fast Associated Control Channel (FACCH) in response to determining that the BER on the uplink and the downlink on the user channel are below the first threshold;

means for estimating the BER on an uplink and a downlink on the FACCH channel;

means for estimating a residual bit error rate (RBER) on the uplink on the FACCH channel;

means for estimating a frame erasure rate (FER) on the uplink on the FACCH channel;

means for determining;

whether the BER on the downlink on the FACCH channel is below a second threshold;

whether the RBER on the uplink is below a third threshold; and

whether the FER on the uplink is equal to zero; and

means for switching the radio telecommunications network from said first grade of service to said second grade of service in response to determining that the BER on the downlink on the FACCH channel is below a second threshold, the RBER on the uplink is below a third threshold, and the FER on the uplink is equal to zero.

2. A method of determining when a radio telecommunications network should switch between a first grade of service and a second grade of service based upon a highly accurate and reliable estimate of the bit error rate (BER), said method comprising the steps of:

estimating the BER on an uplink and a downlink on a user channel;

determining whether the BER on the uplink and the downlink on the user channel are below a first threshold;

sending and receiving a data message on a Fast Associated Control Channel (FACCH) in response to determining that the BER on the uplink and the downlink on the user channel are below the first threshold;

estimating the BER on an uplink and a downlink on the FACCH channel;

estimating a residual bit error rate (RBER) on an uplink on the FACCH channel;

estimating a frame erasure rate (FER) on the uplink on the FACCH channel;

determining whether the BER on the downlink on the FACCH channel is below a second threshold, whether the RBER on the uplink is below a third threshold, and whether the FER on the uplink is equal to zero; and

switching the radio telecommunications network from said first grade of service to said second grade of service in response to determining that the BER on the downlink on the FACCH channel is below a second threshold, the RBER on the uplink is below a third threshold, and the FER on the uplink is equal to zero.