Tejas should use filters on equipment to resolve interference issue: Airtel

Bharti Airtel urges Tejas Networks to add filters on BSNL 4G equipment to prevent signal interference affecting Airtel's network in Rajasthan, citing spectrum compliance issues

Bharti Airtel has said that Tejas Networks should use filters on its equipment to ensure it does not radiate signals beyond a limit, in order to resolve interference between Airtel and Bharat Sanchar Nigam’s (BSNL’s) networks across several 4G sites deployed by the latter in Rajasthan.

 

In response to comments from the chief operating officer of Tejas, who said the interference originated because Airtel’s sites were deployed close to BSNL’s — remarks reported by PTI on Tuesday — a spokesperson for Airtel told Business Standard that the claims were “baseless”, saying that towers routinely accommodate two or more operators in close proximity without any network interference.

 

“The claim made by Tejas Networks is baseless. The current problem is more a function of sub-standard equipment that doesn’t conform to Indian spectrum allocation requirements,” the spokesperson said in an email.

 

Radio equipment made by all global vendors for India’s 850 megahertz (MHz) band conforms to Indian frequency allocation requirements. This ensures that signals in the 850 MHz band are turned off within a certain limit and do not interfere with the uplink in the 900 MHz band.

 

“But the radio equipment made by Tejas for the 850 MHz band in India — being used by BSNL — radiates signals beyond those limits, thus interfering with Airtel’s 900 MHz uplink. To resolve the matter, Tejas needs to use a filter to ensure the equipment radiates signals only up to the limit,” the spokesperson added.

 

Tejas Networks said in response to Airtel’s Tuesday statement that BSNL was in the process of deploying additional filters. "BSNL is in the process of deploying additional filters for this purpose and has already implemented them at approximately 1000 sites. Hence the interference observed at a few Airtel sites in the Rajasthan circle is in no way a reflection of the quality or capability of our equipment," Arnob Roy, executive director and chief operating officer said in an emailed response to Business Standard's queries.

 

 The company added that its equipment was compliant with global norms, when two base stations operating in adjacent bands are located in close proximity at neighboring sites, with antennas facing each other, it is essential to implement additional filtering on the antennas to mitigate adjacent channel interference. 

 

According to sources, Airtel had raised the issue of interference at BSNL’s 4G sites in Rajasthan with the telecommunications (telecom) department’s wireless and planning wing back in February.

 

BSNL is using Tejas Networks’ equipment to deploy 4G services across India.

 

A senior sector expert said the issue raised by Airtel was uncommon since equipment makers adhere to standards set by global benchmarks to prevent interference, which can affect call quality for users.

 

The Indian telecom equipment maker had said in a letter to Airtel — quoted by PTI on Monday — that because BSNL’s and Airtel’s 4G sites were deployed close to each other, there was an increased noise floor and insufficient coupling loss.

 

The Tejas executive said the equipment was fully compliant with government standards and on par with radios from other makers, particularly regarding out-of-band emissions.

 

The executive expressed disappointment at Airtel’s claims and said describing the equipment as “sub-standard” was unwarranted.

 

“All radios deployed in the BSNL network are in full compliance with all emissions norms with a very good margin,” the executive said.